| paul@0 | 1 | #!/usr/bin/env python |
| paul@0 | 2 | |
| paul@0 | 3 | """ |
| paul@0 | 4 | Inspect and obtain module structure. |
| paul@0 | 5 | |
| paul@0 | 6 | Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013, |
| paul@0 | 7 | 2014, 2015, 2016 Paul Boddie <paul@boddie.org.uk> |
| paul@0 | 8 | |
| paul@0 | 9 | This program is free software; you can redistribute it and/or modify it under |
| paul@0 | 10 | the terms of the GNU General Public License as published by the Free Software |
| paul@0 | 11 | Foundation; either version 3 of the License, or (at your option) any later |
| paul@0 | 12 | version. |
| paul@0 | 13 | |
| paul@0 | 14 | This program is distributed in the hope that it will be useful, but WITHOUT |
| paul@0 | 15 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| paul@0 | 16 | FOR A PARTICULAR PURPOSE. See the GNU General Public License for more |
| paul@0 | 17 | details. |
| paul@0 | 18 | |
| paul@0 | 19 | You should have received a copy of the GNU General Public License along with |
| paul@0 | 20 | this program. If not, see <http://www.gnu.org/licenses/>. |
| paul@0 | 21 | """ |
| paul@0 | 22 | |
| paul@0 | 23 | from branching import BranchTracker |
| paul@12 | 24 | from common import get_argnames, init_item, predefined_constants |
| paul@26 | 25 | from modules import BasicModule, CacheWritingModule, InspectionNaming |
| paul@3 | 26 | from errors import InspectError |
| paul@0 | 27 | from referencing import Reference |
| paul@12 | 28 | from resolving import NameResolving |
| paul@12 | 29 | from results import AccessRef, InstanceRef, InvocationRef, LiteralSequenceRef, \ |
| paul@12 | 30 | LocalNameRef, NameRef, ResolvedNameRef |
| paul@0 | 31 | import compiler |
| paul@0 | 32 | import sys |
| paul@0 | 33 | |
| paul@26 | 34 | class InspectedModule(BasicModule, CacheWritingModule, NameResolving, InspectionNaming): |
| paul@0 | 35 | |
| paul@0 | 36 | "A module inspector." |
| paul@0 | 37 | |
| paul@0 | 38 | def __init__(self, name, importer): |
| paul@13 | 39 | |
| paul@13 | 40 | "Initialise the module with basic details." |
| paul@13 | 41 | |
| paul@0 | 42 | BasicModule.__init__(self, name, importer) |
| paul@12 | 43 | |
| paul@0 | 44 | self.in_class = False |
| paul@0 | 45 | self.in_conditional = False |
| paul@78 | 46 | self.in_invocation = False |
| paul@0 | 47 | self.global_attr_accesses = {} |
| paul@0 | 48 | |
| paul@0 | 49 | # Usage tracking. |
| paul@0 | 50 | |
| paul@0 | 51 | self.trackers = [] |
| paul@0 | 52 | self.attr_accessor_branches = {} |
| paul@0 | 53 | |
| paul@0 | 54 | def __repr__(self): |
| paul@0 | 55 | return "InspectedModule(%r, %r)" % (self.name, self.importer) |
| paul@0 | 56 | |
| paul@27 | 57 | # Principal methods. |
| paul@27 | 58 | |
| paul@0 | 59 | def parse(self, filename): |
| paul@0 | 60 | |
| paul@0 | 61 | "Parse the file having the given 'filename'." |
| paul@0 | 62 | |
| paul@0 | 63 | self.parse_file(filename) |
| paul@0 | 64 | |
| paul@0 | 65 | # Inspect the module. |
| paul@0 | 66 | |
| paul@0 | 67 | self.start_tracking_in_module() |
| paul@0 | 68 | |
| paul@0 | 69 | # Detect and record imports and globals declared in the module. |
| paul@0 | 70 | |
| paul@0 | 71 | self.assign_general_local("__name__", self.get_constant("str", self.name)) |
| paul@0 | 72 | self.assign_general_local("__file__", self.get_constant("str", filename)) |
| paul@0 | 73 | self.process_structure(self.astnode) |
| paul@0 | 74 | |
| paul@0 | 75 | # Set the class of the module after the definition has occurred. |
| paul@0 | 76 | |
| paul@0 | 77 | ref = self.get_builtin("object") |
| paul@0 | 78 | self.set_name("__class__", ref) |
| paul@0 | 79 | |
| paul@0 | 80 | # Get module-level attribute usage details. |
| paul@0 | 81 | |
| paul@0 | 82 | self.stop_tracking_in_module() |
| paul@0 | 83 | |
| paul@27 | 84 | # Collect external name references. |
| paul@0 | 85 | |
| paul@27 | 86 | self.collect_names() |
| paul@0 | 87 | |
| paul@12 | 88 | def complete(self): |
| paul@0 | 89 | |
| paul@12 | 90 | "Complete the module inspection." |
| paul@0 | 91 | |
| paul@12 | 92 | # Resolve names not definitively mapped to objects. |
| paul@0 | 93 | |
| paul@12 | 94 | self.resolve() |
| paul@0 | 95 | |
| paul@12 | 96 | # Define the invocation requirements in each namespace. |
| paul@0 | 97 | |
| paul@12 | 98 | self.set_invocation_usage() |
| paul@0 | 99 | |
| paul@12 | 100 | # Propagate to the importer information needed in subsequent activities. |
| paul@0 | 101 | |
| paul@12 | 102 | self.propagate() |
| paul@0 | 103 | |
| paul@27 | 104 | # Accessory methods. |
| paul@0 | 105 | |
| paul@27 | 106 | def collect_names(self): |
| paul@0 | 107 | |
| paul@27 | 108 | "Collect the names used by each scope." |
| paul@0 | 109 | |
| paul@0 | 110 | for path in self.names_used.keys(): |
| paul@27 | 111 | self.collect_names_for_path(path) |
| paul@27 | 112 | |
| paul@27 | 113 | def collect_names_for_path(self, path): |
| paul@0 | 114 | |
| paul@33 | 115 | """ |
| paul@33 | 116 | Collect the names used by the given 'path'. These are propagated to the |
| paul@33 | 117 | importer in advance of any dependency resolution. |
| paul@33 | 118 | """ |
| paul@0 | 119 | |
| paul@0 | 120 | names = self.names_used.get(path) |
| paul@0 | 121 | if not names: |
| paul@0 | 122 | return |
| paul@0 | 123 | |
| paul@0 | 124 | in_function = self.function_locals.has_key(path) |
| paul@0 | 125 | |
| paul@0 | 126 | for name in names: |
| paul@0 | 127 | if name in predefined_constants or in_function and name in self.function_locals[path]: |
| paul@0 | 128 | continue |
| paul@0 | 129 | |
| paul@35 | 130 | # Find local definitions (within dynamic namespaces). |
| paul@0 | 131 | |
| paul@0 | 132 | key = "%s.%s" % (path, name) |
| paul@27 | 133 | ref = self.get_resolved_object(key) |
| paul@0 | 134 | if ref: |
| paul@40 | 135 | self.set_name_reference(key, ref) |
| paul@0 | 136 | continue |
| paul@0 | 137 | |
| paul@40 | 138 | # Find global or known built-in definitions. |
| paul@0 | 139 | |
| paul@27 | 140 | ref = self.get_resolved_global_or_builtin(name) |
| paul@27 | 141 | if ref: |
| paul@40 | 142 | self.set_name_reference(key, ref) |
| paul@0 | 143 | continue |
| paul@0 | 144 | |
| paul@40 | 145 | # Find presumed built-in definitions. |
| paul@0 | 146 | |
| paul@40 | 147 | ref = self.get_builtin(name) |
| paul@40 | 148 | self.set_name_reference(key, ref) |
| paul@0 | 149 | |
| paul@40 | 150 | def set_name_reference(self, path, ref): |
| paul@0 | 151 | |
| paul@40 | 152 | "Map the given name 'path' to 'ref'." |
| paul@0 | 153 | |
| paul@40 | 154 | self.importer.all_name_references[path] = self.name_references[path] = ref |
| paul@0 | 155 | |
| paul@27 | 156 | def get_resolved_global_or_builtin(self, name): |
| paul@0 | 157 | |
| paul@27 | 158 | "Return the resolved global or built-in object with the given 'name'." |
| paul@0 | 159 | |
| paul@40 | 160 | # In some circumstances, the name is neither global nor recognised by |
| paul@40 | 161 | # the importer. It is then assumed to be a general built-in. |
| paul@0 | 162 | |
| paul@40 | 163 | return self.get_global(name) or \ |
| paul@40 | 164 | self.importer.get_object("__builtins__.%s" % name) |
| paul@0 | 165 | |
| paul@0 | 166 | # Module structure traversal. |
| paul@0 | 167 | |
| paul@0 | 168 | def process_structure_node(self, n): |
| paul@0 | 169 | |
| paul@0 | 170 | "Process the individual node 'n'." |
| paul@0 | 171 | |
| paul@0 | 172 | # Module global detection. |
| paul@0 | 173 | |
| paul@0 | 174 | if isinstance(n, compiler.ast.Global): |
| paul@0 | 175 | self.process_global_node(n) |
| paul@0 | 176 | |
| paul@0 | 177 | # Module import declarations. |
| paul@0 | 178 | |
| paul@0 | 179 | elif isinstance(n, compiler.ast.From): |
| paul@0 | 180 | self.process_from_node(n) |
| paul@0 | 181 | |
| paul@0 | 182 | elif isinstance(n, compiler.ast.Import): |
| paul@0 | 183 | self.process_import_node(n) |
| paul@0 | 184 | |
| paul@0 | 185 | # Nodes using operator module functions. |
| paul@0 | 186 | |
| paul@0 | 187 | elif isinstance(n, compiler.ast.Operator): |
| paul@0 | 188 | return self.process_operator_node(n) |
| paul@0 | 189 | |
| paul@0 | 190 | elif isinstance(n, compiler.ast.AugAssign): |
| paul@0 | 191 | self.process_augassign_node(n) |
| paul@0 | 192 | |
| paul@0 | 193 | elif isinstance(n, compiler.ast.Compare): |
| paul@0 | 194 | return self.process_compare_node(n) |
| paul@0 | 195 | |
| paul@0 | 196 | elif isinstance(n, compiler.ast.Slice): |
| paul@0 | 197 | return self.process_slice_node(n) |
| paul@0 | 198 | |
| paul@0 | 199 | elif isinstance(n, compiler.ast.Sliceobj): |
| paul@0 | 200 | return self.process_sliceobj_node(n) |
| paul@0 | 201 | |
| paul@0 | 202 | elif isinstance(n, compiler.ast.Subscript): |
| paul@0 | 203 | return self.process_subscript_node(n) |
| paul@0 | 204 | |
| paul@0 | 205 | # Namespaces within modules. |
| paul@0 | 206 | |
| paul@0 | 207 | elif isinstance(n, compiler.ast.Class): |
| paul@0 | 208 | self.process_class_node(n) |
| paul@0 | 209 | |
| paul@0 | 210 | elif isinstance(n, compiler.ast.Function): |
| paul@0 | 211 | self.process_function_node(n, n.name) |
| paul@0 | 212 | |
| paul@0 | 213 | elif isinstance(n, compiler.ast.Lambda): |
| paul@0 | 214 | return self.process_lambda_node(n) |
| paul@0 | 215 | |
| paul@0 | 216 | # Assignments. |
| paul@0 | 217 | |
| paul@0 | 218 | elif isinstance(n, compiler.ast.Assign): |
| paul@0 | 219 | |
| paul@0 | 220 | # Handle each assignment node. |
| paul@0 | 221 | |
| paul@0 | 222 | for node in n.nodes: |
| paul@0 | 223 | self.process_assignment_node(node, n.expr) |
| paul@0 | 224 | |
| paul@0 | 225 | # Assignments within non-Assign nodes. |
| paul@0 | 226 | |
| paul@0 | 227 | elif isinstance(n, compiler.ast.AssName): |
| paul@0 | 228 | self.process_assignment_node(n, None) |
| paul@0 | 229 | |
| paul@0 | 230 | elif isinstance(n, compiler.ast.AssAttr): |
| paul@0 | 231 | self.process_attribute_access(n) |
| paul@0 | 232 | |
| paul@0 | 233 | # Accesses. |
| paul@0 | 234 | |
| paul@0 | 235 | elif isinstance(n, compiler.ast.Getattr): |
| paul@0 | 236 | return self.process_attribute_access(n) |
| paul@0 | 237 | |
| paul@0 | 238 | # Name recording for later testing. |
| paul@0 | 239 | |
| paul@0 | 240 | elif isinstance(n, compiler.ast.Name): |
| paul@0 | 241 | return self.process_name_node(n) |
| paul@0 | 242 | |
| paul@0 | 243 | # Conditional statement tracking. |
| paul@0 | 244 | |
| paul@0 | 245 | elif isinstance(n, compiler.ast.For): |
| paul@0 | 246 | self.process_for_node(n) |
| paul@0 | 247 | |
| paul@0 | 248 | elif isinstance(n, compiler.ast.While): |
| paul@0 | 249 | self.process_while_node(n) |
| paul@0 | 250 | |
| paul@0 | 251 | elif isinstance(n, compiler.ast.If): |
| paul@0 | 252 | self.process_if_node(n) |
| paul@0 | 253 | |
| paul@0 | 254 | elif isinstance(n, (compiler.ast.And, compiler.ast.Or)): |
| paul@0 | 255 | return self.process_logical_node(n) |
| paul@0 | 256 | |
| paul@0 | 257 | # Exception control-flow tracking. |
| paul@0 | 258 | |
| paul@0 | 259 | elif isinstance(n, compiler.ast.TryExcept): |
| paul@0 | 260 | self.process_try_node(n) |
| paul@0 | 261 | |
| paul@0 | 262 | elif isinstance(n, compiler.ast.TryFinally): |
| paul@0 | 263 | self.process_try_finally_node(n) |
| paul@0 | 264 | |
| paul@0 | 265 | # Control-flow modification statements. |
| paul@0 | 266 | |
| paul@0 | 267 | elif isinstance(n, compiler.ast.Break): |
| paul@0 | 268 | self.trackers[-1].suspend_broken_branch() |
| paul@0 | 269 | |
| paul@0 | 270 | elif isinstance(n, compiler.ast.Continue): |
| paul@0 | 271 | self.trackers[-1].suspend_continuing_branch() |
| paul@0 | 272 | |
| paul@0 | 273 | elif isinstance(n, compiler.ast.Raise): |
| paul@0 | 274 | self.process_structure(n) |
| paul@0 | 275 | self.trackers[-1].abandon_branch() |
| paul@0 | 276 | |
| paul@0 | 277 | elif isinstance(n, compiler.ast.Return): |
| paul@0 | 278 | self.process_structure(n) |
| paul@0 | 279 | self.trackers[-1].abandon_returning_branch() |
| paul@0 | 280 | |
| paul@0 | 281 | # Invocations. |
| paul@0 | 282 | |
| paul@0 | 283 | elif isinstance(n, compiler.ast.CallFunc): |
| paul@0 | 284 | return self.process_invocation_node(n) |
| paul@0 | 285 | |
| paul@0 | 286 | # Constant usage. |
| paul@0 | 287 | |
| paul@0 | 288 | elif isinstance(n, compiler.ast.Const): |
| paul@0 | 289 | return self.get_literal_instance(n, n.value.__class__.__name__) |
| paul@0 | 290 | |
| paul@0 | 291 | elif isinstance(n, compiler.ast.Dict): |
| paul@0 | 292 | return self.get_literal_instance(n, "dict") |
| paul@0 | 293 | |
| paul@0 | 294 | elif isinstance(n, compiler.ast.List): |
| paul@0 | 295 | return self.get_literal_instance(n, "list") |
| paul@0 | 296 | |
| paul@0 | 297 | elif isinstance(n, compiler.ast.Tuple): |
| paul@0 | 298 | return self.get_literal_instance(n, "tuple") |
| paul@0 | 299 | |
| paul@3 | 300 | # Unsupported nodes. |
| paul@3 | 301 | |
| paul@3 | 302 | elif isinstance(n, compiler.ast.GenExpr): |
| paul@3 | 303 | raise InspectError("Generator expressions are not supported.", self.get_namespace_path(), n) |
| paul@3 | 304 | |
| paul@3 | 305 | elif isinstance(n, compiler.ast.IfExp): |
| paul@3 | 306 | raise InspectError("If-else expressions are not supported.", self.get_namespace_path(), n) |
| paul@0 | 307 | |
| paul@0 | 308 | elif isinstance(n, compiler.ast.ListComp): |
| paul@3 | 309 | raise InspectError("List comprehensions are not supported.", self.get_namespace_path(), n) |
| paul@0 | 310 | |
| paul@0 | 311 | # All other nodes are processed depth-first. |
| paul@0 | 312 | |
| paul@0 | 313 | else: |
| paul@0 | 314 | self.process_structure(n) |
| paul@0 | 315 | |
| paul@0 | 316 | # By default, no expression details are returned. |
| paul@0 | 317 | |
| paul@0 | 318 | return None |
| paul@0 | 319 | |
| paul@0 | 320 | # Specific node handling. |
| paul@0 | 321 | |
| paul@0 | 322 | def process_assignment_node(self, n, expr): |
| paul@0 | 323 | |
| paul@0 | 324 | "Process the individual node 'n' to be assigned the contents of 'expr'." |
| paul@0 | 325 | |
| paul@0 | 326 | # Names and attributes are assigned the entire expression. |
| paul@0 | 327 | |
| paul@0 | 328 | if isinstance(n, compiler.ast.AssName): |
| paul@61 | 329 | if n.name == "self": |
| paul@61 | 330 | raise InspectError("Redefinition of self is not allowed.", self.get_namespace_path(), n) |
| paul@0 | 331 | |
| paul@0 | 332 | name_ref = expr and self.process_structure_node(expr) |
| paul@0 | 333 | |
| paul@0 | 334 | # Name assignments populate either function namespaces or the |
| paul@0 | 335 | # general namespace hierarchy. |
| paul@0 | 336 | |
| paul@0 | 337 | self.assign_general_local(n.name, name_ref) |
| paul@0 | 338 | |
| paul@0 | 339 | # Record usage of the name. |
| paul@0 | 340 | |
| paul@0 | 341 | self.record_name(n.name) |
| paul@0 | 342 | |
| paul@0 | 343 | elif isinstance(n, compiler.ast.AssAttr): |
| paul@0 | 344 | if expr: self.process_structure_node(expr) |
| paul@0 | 345 | self.process_attribute_access(n) |
| paul@0 | 346 | |
| paul@0 | 347 | # Lists and tuples are matched against the expression and their |
| paul@0 | 348 | # items assigned to expression items. |
| paul@0 | 349 | |
| paul@0 | 350 | elif isinstance(n, (compiler.ast.AssList, compiler.ast.AssTuple)): |
| paul@0 | 351 | self.process_assignment_node_items(n, expr) |
| paul@0 | 352 | |
| paul@0 | 353 | # Slices and subscripts are permitted within assignment nodes. |
| paul@0 | 354 | |
| paul@0 | 355 | elif isinstance(n, compiler.ast.Slice): |
| paul@0 | 356 | self.process_slice_node(n, expr) |
| paul@0 | 357 | |
| paul@0 | 358 | elif isinstance(n, compiler.ast.Subscript): |
| paul@0 | 359 | self.process_subscript_node(n, expr) |
| paul@0 | 360 | |
| paul@0 | 361 | def process_attribute_access(self, n): |
| paul@0 | 362 | |
| paul@0 | 363 | "Process the given attribute access node 'n'." |
| paul@0 | 364 | |
| paul@0 | 365 | # Obtain any completed chain and return the reference to it. |
| paul@0 | 366 | |
| paul@0 | 367 | name_ref = self.process_attribute_chain(n) |
| paul@0 | 368 | if self.have_access_expression(n): |
| paul@0 | 369 | return name_ref |
| paul@0 | 370 | |
| paul@0 | 371 | # Where the start of the chain of attributes has been reached, determine |
| paul@0 | 372 | # the complete access. |
| paul@0 | 373 | |
| paul@0 | 374 | # Given a non-access node, this chain can be handled in its entirety, |
| paul@0 | 375 | # either being name-based and thus an access rooted on a name, or being |
| paul@0 | 376 | # based on some other node and thus an anonymous access of some kind. |
| paul@0 | 377 | |
| paul@0 | 378 | path = self.get_namespace_path() |
| paul@0 | 379 | |
| paul@0 | 380 | # Start with the the full attribute chain. |
| paul@0 | 381 | |
| paul@0 | 382 | remaining = self.attrs |
| paul@0 | 383 | attrnames = ".".join(remaining) |
| paul@0 | 384 | |
| paul@0 | 385 | # If the accessor cannot be identified, or where attributes |
| paul@0 | 386 | # remain in an attribute chain, record the anonymous accesses. |
| paul@0 | 387 | |
| paul@0 | 388 | if not isinstance(name_ref, NameRef): # includes ResolvedNameRef |
| paul@0 | 389 | |
| paul@0 | 390 | assignment = isinstance(n, compiler.ast.AssAttr) |
| paul@0 | 391 | |
| paul@0 | 392 | init_item(self.attr_accesses, path, set) |
| paul@0 | 393 | self.attr_accesses[path].add(attrnames) |
| paul@0 | 394 | |
| paul@0 | 395 | self.record_access_details(None, attrnames, assignment) |
| paul@0 | 396 | del self.attrs[0] |
| paul@0 | 397 | return |
| paul@0 | 398 | |
| paul@0 | 399 | # Name-based accesses will handle the first attribute in a |
| paul@0 | 400 | # chain. |
| paul@0 | 401 | |
| paul@0 | 402 | else: |
| paul@0 | 403 | attrname = remaining[0] |
| paul@0 | 404 | |
| paul@0 | 405 | # Attribute assignments are used to identify instance attributes. |
| paul@0 | 406 | |
| paul@0 | 407 | if isinstance(n, compiler.ast.AssAttr) and \ |
| paul@0 | 408 | self.in_class and self.in_function and n.expr.name == "self": |
| paul@0 | 409 | |
| paul@0 | 410 | self.set_instance_attr(attrname) |
| paul@0 | 411 | |
| paul@0 | 412 | # Record attribute usage using any name local to this namespace, |
| paul@0 | 413 | # if assigned in the namespace, or using an external name |
| paul@0 | 414 | # (presently just globals within classes). |
| paul@0 | 415 | |
| paul@0 | 416 | name = self.get_name_for_tracking(name_ref.name, name_ref.final()) |
| paul@0 | 417 | tracker = self.trackers[-1] |
| paul@0 | 418 | |
| paul@0 | 419 | immediate_access = len(self.attrs) == 1 |
| paul@0 | 420 | assignment = immediate_access and isinstance(n, compiler.ast.AssAttr) |
| paul@0 | 421 | |
| paul@0 | 422 | del self.attrs[0] |
| paul@0 | 423 | |
| paul@0 | 424 | # Record global-based chains for subsequent resolution. |
| paul@0 | 425 | |
| paul@0 | 426 | is_global = self.in_function and not self.function_locals[path].has_key(name) or \ |
| paul@0 | 427 | not self.in_function |
| paul@0 | 428 | |
| paul@0 | 429 | if is_global: |
| paul@0 | 430 | self.record_global_access_details(name, attrnames) |
| paul@0 | 431 | |
| paul@0 | 432 | # Make sure the name is being tracked: global names will not |
| paul@0 | 433 | # already be initialised in a branch and must be added |
| paul@0 | 434 | # explicitly. |
| paul@0 | 435 | |
| paul@0 | 436 | if not tracker.have_name(name): |
| paul@0 | 437 | tracker.assign_names([name]) |
| paul@0 | 438 | if self.in_function: |
| paul@0 | 439 | self.scope_globals[path].add(name) |
| paul@0 | 440 | |
| paul@0 | 441 | # Record attribute usage in the tracker, and record the branch |
| paul@0 | 442 | # information for the access. |
| paul@0 | 443 | |
| paul@0 | 444 | branches = tracker.use_attribute(name, attrname) |
| paul@0 | 445 | |
| paul@0 | 446 | if not branches: |
| paul@0 | 447 | print >>sys.stderr, "In %s, name %s is accessed using %s before an assignment." % ( |
| paul@0 | 448 | path, name, attrname) |
| paul@0 | 449 | branches = tracker.use_attribute(name, attrname) |
| paul@0 | 450 | |
| paul@0 | 451 | self.record_branches_for_access(branches, name, attrnames) |
| paul@0 | 452 | access_number = self.record_access_details(name, attrnames, assignment) |
| paul@0 | 453 | return AccessRef(name, attrnames, access_number) |
| paul@0 | 454 | |
| paul@0 | 455 | def process_class_node(self, n): |
| paul@0 | 456 | |
| paul@0 | 457 | "Process the given class node 'n'." |
| paul@0 | 458 | |
| paul@0 | 459 | path = self.get_namespace_path() |
| paul@0 | 460 | |
| paul@0 | 461 | # To avoid notions of class "versions" where the same definition |
| paul@0 | 462 | # might be parameterised with different state and be referenced |
| paul@0 | 463 | # elsewhere (as base classes, for example), classes in functions or |
| paul@0 | 464 | # conditions are forbidden. |
| paul@0 | 465 | |
| paul@0 | 466 | if self.in_function or self.in_conditional: |
| paul@0 | 467 | print >>sys.stderr, "In %s, class %s in function or conditional statement ignored." % ( |
| paul@0 | 468 | path, n.name) |
| paul@0 | 469 | return |
| paul@0 | 470 | |
| paul@0 | 471 | # Resolve base classes. |
| paul@0 | 472 | |
| paul@0 | 473 | bases = [] |
| paul@0 | 474 | |
| paul@0 | 475 | for base in n.bases: |
| paul@0 | 476 | base_class = self.get_class(base) |
| paul@0 | 477 | |
| paul@0 | 478 | if not base_class: |
| paul@12 | 479 | print >>sys.stderr, "In %s, class %s has unidentifiable base class: %s" % ( |
| paul@12 | 480 | path, n.name, base) |
| paul@0 | 481 | return |
| paul@0 | 482 | else: |
| paul@0 | 483 | bases.append(base_class) |
| paul@0 | 484 | |
| paul@0 | 485 | # Record bases for the class and retain the class name. |
| paul@0 | 486 | |
| paul@0 | 487 | class_name = self.get_object_path(n.name) |
| paul@0 | 488 | |
| paul@0 | 489 | if not bases and class_name != "__builtins__.core.object": |
| paul@0 | 490 | ref = self.get_object("__builtins__.object") |
| paul@0 | 491 | bases.append(ref) |
| paul@0 | 492 | |
| paul@0 | 493 | self.importer.classes[class_name] = self.classes[class_name] = bases |
| paul@0 | 494 | self.importer.subclasses[class_name] = set() |
| paul@0 | 495 | self.scope_globals[class_name] = set() |
| paul@0 | 496 | |
| paul@0 | 497 | # Set the definition before entering the namespace rather than |
| paul@0 | 498 | # afterwards because methods may reference it. In normal Python, |
| paul@0 | 499 | # a class is not accessible until the definition is complete, but |
| paul@0 | 500 | # methods can generally reference it since upon being called the |
| paul@0 | 501 | # class will already exist. |
| paul@0 | 502 | |
| paul@0 | 503 | self.set_definition(n.name, "<class>") |
| paul@0 | 504 | |
| paul@0 | 505 | in_class = self.in_class |
| paul@0 | 506 | self.in_class = class_name |
| paul@0 | 507 | self.set_instance_attr("__class__", Reference("<class>", class_name)) |
| paul@0 | 508 | self.enter_namespace(n.name) |
| paul@0 | 509 | self.set_name("__fn__") # special instantiator attribute |
| paul@0 | 510 | self.set_name("__args__") # special instantiator attribute |
| paul@0 | 511 | self.assign_general_local("__name__", self.get_constant("str", class_name)) |
| paul@0 | 512 | self.process_structure_node(n.code) |
| paul@0 | 513 | self.exit_namespace() |
| paul@0 | 514 | self.in_class = in_class |
| paul@0 | 515 | |
| paul@0 | 516 | def process_from_node(self, n): |
| paul@0 | 517 | |
| paul@0 | 518 | "Process the given node 'n', importing from another module." |
| paul@0 | 519 | |
| paul@0 | 520 | path = self.get_namespace_path() |
| paul@0 | 521 | |
| paul@12 | 522 | module_name, names = self.get_module_name(n) |
| paul@12 | 523 | if module_name == self.name: |
| paul@12 | 524 | raise InspectError("Cannot import from the current module.", path, n) |
| paul@0 | 525 | |
| paul@18 | 526 | self.queue_module(module_name) |
| paul@0 | 527 | |
| paul@0 | 528 | # Attempt to obtain the referenced objects. |
| paul@0 | 529 | |
| paul@0 | 530 | for name, alias in n.names: |
| paul@0 | 531 | if name == "*": |
| paul@12 | 532 | raise InspectError("Only explicitly specified names can be imported from modules.", path, n) |
| paul@0 | 533 | |
| paul@0 | 534 | # Explicit names. |
| paul@0 | 535 | |
| paul@12 | 536 | ref = self.import_name_from_module(name, module_name) |
| paul@0 | 537 | value = ResolvedNameRef(alias or name, ref) |
| paul@0 | 538 | self.set_general_local(alias or name, value) |
| paul@0 | 539 | |
| paul@0 | 540 | def process_function_node(self, n, name): |
| paul@0 | 541 | |
| paul@0 | 542 | """ |
| paul@0 | 543 | Process the given function or lambda node 'n' with the given 'name'. |
| paul@0 | 544 | """ |
| paul@0 | 545 | |
| paul@0 | 546 | is_lambda = isinstance(n, compiler.ast.Lambda) |
| paul@0 | 547 | |
| paul@0 | 548 | # Where a function is declared conditionally, use a separate name for |
| paul@0 | 549 | # the definition, and assign the definition to the stated name. |
| paul@0 | 550 | |
| paul@0 | 551 | if (self.in_conditional or self.in_function) and not is_lambda: |
| paul@0 | 552 | original_name = name |
| paul@0 | 553 | name = self.get_lambda_name() |
| paul@0 | 554 | else: |
| paul@0 | 555 | original_name = None |
| paul@0 | 556 | |
| paul@0 | 557 | # Initialise argument and local records. |
| paul@0 | 558 | |
| paul@0 | 559 | function_name = self.get_object_path(name) |
| paul@46 | 560 | argnames = get_argnames(n.argnames) |
| paul@48 | 561 | is_method = self.in_class and not self.in_function |
| paul@0 | 562 | |
| paul@48 | 563 | # Remove explicit "self" from method parameters. |
| paul@46 | 564 | |
| paul@48 | 565 | if is_method and argnames and argnames[0] == "self": |
| paul@48 | 566 | del argnames[0] |
| paul@48 | 567 | |
| paul@48 | 568 | # Copy and propagate the parameters. |
| paul@46 | 569 | |
| paul@46 | 570 | self.importer.function_parameters[function_name] = \ |
| paul@48 | 571 | self.function_parameters[function_name] = argnames[:] |
| paul@46 | 572 | |
| paul@46 | 573 | # Define all arguments/parameters in the local namespace. |
| paul@46 | 574 | |
| paul@0 | 575 | locals = self.function_locals[function_name] = {} |
| paul@0 | 576 | |
| paul@48 | 577 | # Insert "self" into method locals. |
| paul@48 | 578 | |
| paul@48 | 579 | if is_method: |
| paul@48 | 580 | argnames.insert(0, "self") |
| paul@48 | 581 | |
| paul@47 | 582 | # Define "self" in terms of the class if in a method. |
| paul@47 | 583 | # This does not diminish the need for type-narrowing in the deducer. |
| paul@47 | 584 | |
| paul@47 | 585 | if argnames: |
| paul@48 | 586 | if self.in_class and not self.in_function and argnames[0] == "self": |
| paul@47 | 587 | locals[argnames[0]] = Reference("<instance>", self.in_class) |
| paul@47 | 588 | else: |
| paul@47 | 589 | locals[argnames[0]] = Reference("<var>") |
| paul@47 | 590 | |
| paul@47 | 591 | for argname in argnames[1:]: |
| paul@0 | 592 | locals[argname] = Reference("<var>") |
| paul@0 | 593 | |
| paul@0 | 594 | globals = self.scope_globals[function_name] = set() |
| paul@0 | 595 | |
| paul@0 | 596 | # Process the defaults. |
| paul@0 | 597 | |
| paul@0 | 598 | defaults = self.importer.function_defaults[function_name] = \ |
| paul@0 | 599 | self.function_defaults[function_name] = [] |
| paul@0 | 600 | |
| paul@0 | 601 | for argname, default in compiler.ast.get_defaults(n): |
| paul@0 | 602 | if default: |
| paul@0 | 603 | |
| paul@0 | 604 | # Obtain any reference for the default. |
| paul@0 | 605 | |
| paul@0 | 606 | name_ref = self.process_structure_node(default) |
| paul@0 | 607 | defaults.append((argname, name_ref.is_name() and name_ref.reference() or Reference("<var>"))) |
| paul@0 | 608 | |
| paul@0 | 609 | # Reset conditional tracking to focus on the function contents. |
| paul@0 | 610 | |
| paul@0 | 611 | in_conditional = self.in_conditional |
| paul@0 | 612 | self.in_conditional = False |
| paul@0 | 613 | |
| paul@0 | 614 | in_function = self.in_function |
| paul@0 | 615 | self.in_function = function_name |
| paul@0 | 616 | |
| paul@0 | 617 | self.enter_namespace(name) |
| paul@0 | 618 | |
| paul@0 | 619 | # Track attribute usage within the namespace. |
| paul@0 | 620 | |
| paul@0 | 621 | path = self.get_namespace_path() |
| paul@0 | 622 | |
| paul@0 | 623 | self.start_tracking(locals) |
| paul@0 | 624 | self.process_structure_node(n.code) |
| paul@0 | 625 | self.stop_tracking() |
| paul@0 | 626 | |
| paul@1 | 627 | # Exit to the parent. |
| paul@0 | 628 | |
| paul@0 | 629 | self.exit_namespace() |
| paul@0 | 630 | |
| paul@0 | 631 | # Update flags. |
| paul@0 | 632 | |
| paul@0 | 633 | self.in_function = in_function |
| paul@0 | 634 | self.in_conditional = in_conditional |
| paul@0 | 635 | |
| paul@0 | 636 | # Define the function using the appropriate name. |
| paul@0 | 637 | |
| paul@0 | 638 | self.set_definition(name, "<function>") |
| paul@0 | 639 | |
| paul@0 | 640 | # Where a function is set conditionally, assign the name. |
| paul@0 | 641 | |
| paul@0 | 642 | if original_name: |
| paul@0 | 643 | self.process_assignment_for_function(original_name, name) |
| paul@0 | 644 | |
| paul@0 | 645 | def process_global_node(self, n): |
| paul@0 | 646 | |
| paul@0 | 647 | """ |
| paul@0 | 648 | Process the given "global" node 'n'. |
| paul@0 | 649 | """ |
| paul@0 | 650 | |
| paul@0 | 651 | path = self.get_namespace_path() |
| paul@0 | 652 | |
| paul@0 | 653 | if path != self.name: |
| paul@0 | 654 | self.scope_globals[path].update(n.names) |
| paul@0 | 655 | |
| paul@0 | 656 | def process_if_node(self, n): |
| paul@0 | 657 | |
| paul@0 | 658 | """ |
| paul@0 | 659 | Process the given "if" node 'n'. |
| paul@0 | 660 | """ |
| paul@0 | 661 | |
| paul@0 | 662 | tracker = self.trackers[-1] |
| paul@0 | 663 | tracker.new_branchpoint() |
| paul@0 | 664 | |
| paul@0 | 665 | for test, body in n.tests: |
| paul@0 | 666 | self.process_structure_node(test) |
| paul@0 | 667 | |
| paul@0 | 668 | tracker.new_branch() |
| paul@0 | 669 | |
| paul@0 | 670 | in_conditional = self.in_conditional |
| paul@0 | 671 | self.in_conditional = True |
| paul@0 | 672 | self.process_structure_node(body) |
| paul@0 | 673 | self.in_conditional = in_conditional |
| paul@0 | 674 | |
| paul@0 | 675 | tracker.shelve_branch() |
| paul@0 | 676 | |
| paul@0 | 677 | # Maintain a branch for the else clause. |
| paul@0 | 678 | |
| paul@0 | 679 | tracker.new_branch() |
| paul@0 | 680 | if n.else_: |
| paul@0 | 681 | self.process_structure_node(n.else_) |
| paul@0 | 682 | tracker.shelve_branch() |
| paul@0 | 683 | |
| paul@0 | 684 | tracker.merge_branches() |
| paul@0 | 685 | |
| paul@0 | 686 | def process_import_node(self, n): |
| paul@0 | 687 | |
| paul@0 | 688 | "Process the given import node 'n'." |
| paul@0 | 689 | |
| paul@0 | 690 | path = self.get_namespace_path() |
| paul@0 | 691 | |
| paul@0 | 692 | # Load the mentioned module. |
| paul@0 | 693 | |
| paul@0 | 694 | for name, alias in n.names: |
| paul@12 | 695 | if name == self.name: |
| paul@12 | 696 | raise InspectError("Cannot import the current module.", path, n) |
| paul@0 | 697 | |
| paul@13 | 698 | self.set_module(alias or name.split(".")[-1], name) |
| paul@18 | 699 | self.queue_module(name, True) |
| paul@0 | 700 | |
| paul@0 | 701 | def process_invocation_node(self, n): |
| paul@0 | 702 | |
| paul@0 | 703 | "Process the given invocation node 'n'." |
| paul@0 | 704 | |
| paul@0 | 705 | path = self.get_namespace_path() |
| paul@0 | 706 | |
| paul@0 | 707 | self.allocate_arguments(path, n.args) |
| paul@0 | 708 | |
| paul@0 | 709 | try: |
| paul@0 | 710 | # Process the expression, obtaining any identified reference. |
| paul@0 | 711 | |
| paul@78 | 712 | in_invocation = self.in_invocation |
| paul@78 | 713 | self.in_invocation = True |
| paul@0 | 714 | name_ref = self.process_structure_node(n.node) |
| paul@78 | 715 | self.in_invocation = in_invocation |
| paul@0 | 716 | |
| paul@0 | 717 | # Process the arguments. |
| paul@0 | 718 | |
| paul@0 | 719 | for arg in n.args: |
| paul@0 | 720 | self.process_structure_node(arg) |
| paul@0 | 721 | |
| paul@0 | 722 | # Detect class invocations. |
| paul@0 | 723 | |
| paul@0 | 724 | if isinstance(name_ref, ResolvedNameRef) and name_ref.has_kind("<class>"): |
| paul@0 | 725 | return InstanceRef(name_ref.reference().instance_of()) |
| paul@0 | 726 | |
| paul@0 | 727 | elif isinstance(name_ref, NameRef): |
| paul@0 | 728 | return InvocationRef(name_ref) |
| paul@0 | 729 | |
| paul@0 | 730 | return None |
| paul@0 | 731 | |
| paul@0 | 732 | finally: |
| paul@0 | 733 | self.deallocate_arguments(path, n.args) |
| paul@0 | 734 | |
| paul@0 | 735 | def process_lambda_node(self, n): |
| paul@0 | 736 | |
| paul@0 | 737 | "Process the given lambda node 'n'." |
| paul@0 | 738 | |
| paul@0 | 739 | name = self.get_lambda_name() |
| paul@0 | 740 | self.process_function_node(n, name) |
| paul@0 | 741 | |
| paul@0 | 742 | origin = self.get_object_path(name) |
| paul@0 | 743 | return ResolvedNameRef(name, Reference("<function>", origin)) |
| paul@0 | 744 | |
| paul@0 | 745 | def process_logical_node(self, n): |
| paul@0 | 746 | |
| paul@0 | 747 | "Process the given operator node 'n'." |
| paul@0 | 748 | |
| paul@0 | 749 | self.process_operator_chain(n.nodes, self.process_structure_node) |
| paul@0 | 750 | |
| paul@0 | 751 | def process_name_node(self, n): |
| paul@0 | 752 | |
| paul@0 | 753 | "Process the given name node 'n'." |
| paul@0 | 754 | |
| paul@0 | 755 | path = self.get_namespace_path() |
| paul@0 | 756 | |
| paul@0 | 757 | # Special names. |
| paul@0 | 758 | |
| paul@0 | 759 | if n.name.startswith("$"): |
| paul@0 | 760 | value = self.get_special(n.name) |
| paul@0 | 761 | if value: |
| paul@0 | 762 | return value |
| paul@0 | 763 | |
| paul@0 | 764 | # Special case for operator functions introduced through code |
| paul@0 | 765 | # transformations. |
| paul@0 | 766 | |
| paul@0 | 767 | if n.name.startswith("$op"): |
| paul@0 | 768 | |
| paul@0 | 769 | # Obtain the location of the actual function defined in the operator |
| paul@0 | 770 | # package. |
| paul@0 | 771 | |
| paul@0 | 772 | op = n.name[len("$op"):] |
| paul@0 | 773 | |
| paul@0 | 774 | # Attempt to get a reference. |
| paul@0 | 775 | |
| paul@12 | 776 | ref = self.import_name_from_module(op, "operator") |
| paul@35 | 777 | self.add_deferred(ref) |
| paul@0 | 778 | |
| paul@0 | 779 | # Record the imported name and provide the resolved name reference. |
| paul@0 | 780 | |
| paul@0 | 781 | value = ResolvedNameRef(n.name, ref) |
| paul@0 | 782 | self.set_special(n.name, value) |
| paul@0 | 783 | return value |
| paul@0 | 784 | |
| paul@60 | 785 | # Test for self usage, which is only allowed in methods. |
| paul@60 | 786 | |
| paul@60 | 787 | if n.name == "self" and not (self.in_function and self.in_class): |
| paul@60 | 788 | raise InspectError("Use of self is only allowed in methods.", path, n) |
| paul@60 | 789 | |
| paul@0 | 790 | # Record usage of the name. |
| paul@0 | 791 | |
| paul@0 | 792 | self.record_name(n.name) |
| paul@0 | 793 | |
| paul@0 | 794 | # Search for unknown names in non-function scopes immediately. |
| paul@0 | 795 | # External names in functions are resolved later. |
| paul@0 | 796 | |
| paul@0 | 797 | ref = self.find_name(n.name) |
| paul@0 | 798 | if ref: |
| paul@0 | 799 | return ResolvedNameRef(n.name, ref) |
| paul@0 | 800 | |
| paul@40 | 801 | # Explicitly-declared global names. |
| paul@0 | 802 | |
| paul@0 | 803 | elif self.in_function and n.name in self.scope_globals[path]: |
| paul@0 | 804 | return NameRef(n.name) |
| paul@0 | 805 | |
| paul@0 | 806 | # Examine other names. |
| paul@0 | 807 | |
| paul@0 | 808 | else: |
| paul@0 | 809 | tracker = self.trackers[-1] |
| paul@0 | 810 | |
| paul@0 | 811 | # Check local names. |
| paul@0 | 812 | |
| paul@0 | 813 | branches = tracker.tracking_name(n.name) |
| paul@0 | 814 | |
| paul@1 | 815 | # Local name. |
| paul@0 | 816 | |
| paul@0 | 817 | if branches: |
| paul@0 | 818 | self.record_branches_for_access(branches, n.name, None) |
| paul@0 | 819 | access_number = self.record_access_details(n.name, None, False) |
| paul@0 | 820 | return LocalNameRef(n.name, access_number) |
| paul@0 | 821 | |
| paul@40 | 822 | # Possible global or built-in name. |
| paul@0 | 823 | |
| paul@0 | 824 | else: |
| paul@0 | 825 | return NameRef(n.name) |
| paul@0 | 826 | |
| paul@0 | 827 | def process_operator_chain(self, nodes, fn): |
| paul@0 | 828 | |
| paul@0 | 829 | """ |
| paul@0 | 830 | Process the given chain of 'nodes', applying 'fn' to each node or item. |
| paul@0 | 831 | Each node starts a new conditional region, effectively making a deeply- |
| paul@0 | 832 | nested collection of if-like statements. |
| paul@0 | 833 | """ |
| paul@0 | 834 | |
| paul@0 | 835 | tracker = self.trackers[-1] |
| paul@0 | 836 | |
| paul@0 | 837 | for item in nodes: |
| paul@0 | 838 | tracker.new_branchpoint() |
| paul@0 | 839 | tracker.new_branch() |
| paul@0 | 840 | fn(item) |
| paul@0 | 841 | |
| paul@0 | 842 | for item in nodes[:-1]: |
| paul@0 | 843 | tracker.shelve_branch() |
| paul@0 | 844 | tracker.new_branch() |
| paul@0 | 845 | tracker.shelve_branch() |
| paul@0 | 846 | tracker.merge_branches() |
| paul@0 | 847 | |
| paul@0 | 848 | tracker.shelve_branch() |
| paul@0 | 849 | tracker.merge_branches() |
| paul@0 | 850 | |
| paul@0 | 851 | def process_try_node(self, n): |
| paul@0 | 852 | |
| paul@0 | 853 | """ |
| paul@0 | 854 | Process the given "try...except" node 'n'. |
| paul@0 | 855 | """ |
| paul@0 | 856 | |
| paul@0 | 857 | tracker = self.trackers[-1] |
| paul@0 | 858 | tracker.new_branchpoint() |
| paul@0 | 859 | |
| paul@0 | 860 | self.process_structure_node(n.body) |
| paul@0 | 861 | |
| paul@0 | 862 | for name, var, handler in n.handlers: |
| paul@0 | 863 | if name is not None: |
| paul@0 | 864 | self.process_structure_node(name) |
| paul@0 | 865 | |
| paul@0 | 866 | # Any abandoned branches from the body can now be resumed in a new |
| paul@0 | 867 | # branch. |
| paul@0 | 868 | |
| paul@0 | 869 | tracker.resume_abandoned_branches() |
| paul@0 | 870 | |
| paul@0 | 871 | # Establish the local for the handler. |
| paul@0 | 872 | |
| paul@0 | 873 | if var is not None: |
| paul@0 | 874 | self.process_structure_node(var) |
| paul@0 | 875 | if handler is not None: |
| paul@0 | 876 | self.process_structure_node(handler) |
| paul@0 | 877 | |
| paul@0 | 878 | tracker.shelve_branch() |
| paul@0 | 879 | |
| paul@0 | 880 | # The else clause maintains the usage from the body but without the |
| paul@0 | 881 | # abandoned branches since they would never lead to the else clause |
| paul@0 | 882 | # being executed. |
| paul@0 | 883 | |
| paul@0 | 884 | if n.else_: |
| paul@0 | 885 | tracker.new_branch() |
| paul@0 | 886 | self.process_structure_node(n.else_) |
| paul@0 | 887 | tracker.shelve_branch() |
| paul@0 | 888 | |
| paul@0 | 889 | # Without an else clause, a null branch propagates the successful |
| paul@0 | 890 | # outcome. |
| paul@0 | 891 | |
| paul@0 | 892 | else: |
| paul@0 | 893 | tracker.new_branch() |
| paul@0 | 894 | tracker.shelve_branch() |
| paul@0 | 895 | |
| paul@0 | 896 | tracker.merge_branches() |
| paul@0 | 897 | |
| paul@0 | 898 | def process_try_finally_node(self, n): |
| paul@0 | 899 | |
| paul@0 | 900 | """ |
| paul@0 | 901 | Process the given "try...finally" node 'n'. |
| paul@0 | 902 | """ |
| paul@0 | 903 | |
| paul@0 | 904 | tracker = self.trackers[-1] |
| paul@0 | 905 | self.process_structure_node(n.body) |
| paul@0 | 906 | |
| paul@0 | 907 | # Any abandoned branches from the body can now be resumed. |
| paul@0 | 908 | |
| paul@0 | 909 | branches = tracker.resume_all_abandoned_branches() |
| paul@0 | 910 | self.process_structure_node(n.final) |
| paul@0 | 911 | |
| paul@0 | 912 | # At the end of the finally clause, abandoned branches are discarded. |
| paul@0 | 913 | |
| paul@0 | 914 | tracker.restore_active_branches(branches) |
| paul@0 | 915 | |
| paul@0 | 916 | def process_while_node(self, n): |
| paul@0 | 917 | |
| paul@0 | 918 | "Process the given while node 'n'." |
| paul@0 | 919 | |
| paul@0 | 920 | tracker = self.trackers[-1] |
| paul@0 | 921 | tracker.new_branchpoint(loop_node=True) |
| paul@0 | 922 | |
| paul@0 | 923 | # Evaluate any test or iterator outside the loop. |
| paul@0 | 924 | |
| paul@0 | 925 | self.process_structure_node(n.test) |
| paul@0 | 926 | |
| paul@0 | 927 | # Propagate attribute usage to branches. |
| paul@0 | 928 | |
| paul@0 | 929 | tracker.new_branch(loop_node=True) |
| paul@0 | 930 | |
| paul@0 | 931 | # Enter the loop. |
| paul@0 | 932 | |
| paul@0 | 933 | in_conditional = self.in_conditional |
| paul@0 | 934 | self.in_conditional = True |
| paul@0 | 935 | self.process_structure_node(n.body) |
| paul@0 | 936 | self.in_conditional = in_conditional |
| paul@0 | 937 | |
| paul@0 | 938 | # Continuing branches are resumed before any test. |
| paul@0 | 939 | |
| paul@0 | 940 | tracker.resume_continuing_branches() |
| paul@0 | 941 | |
| paul@0 | 942 | # Evaluate any continuation test within the body. |
| paul@0 | 943 | |
| paul@0 | 944 | self.process_structure_node(n.test) |
| paul@0 | 945 | |
| paul@0 | 946 | tracker.shelve_branch(loop_node=True) |
| paul@0 | 947 | |
| paul@0 | 948 | # Support the non-looping condition. |
| paul@0 | 949 | |
| paul@0 | 950 | tracker.new_branch() |
| paul@0 | 951 | tracker.shelve_branch() |
| paul@0 | 952 | |
| paul@0 | 953 | tracker.merge_branches() |
| paul@0 | 954 | |
| paul@0 | 955 | # Evaluate any else clause outside branches. |
| paul@0 | 956 | |
| paul@0 | 957 | if n.else_: |
| paul@0 | 958 | self.process_structure_node(n.else_) |
| paul@0 | 959 | |
| paul@0 | 960 | # Connect broken branches to the code after any loop. |
| paul@0 | 961 | |
| paul@0 | 962 | tracker.resume_broken_branches() |
| paul@0 | 963 | |
| paul@0 | 964 | # Branch tracking methods. |
| paul@0 | 965 | |
| paul@0 | 966 | def start_tracking(self, names): |
| paul@0 | 967 | |
| paul@0 | 968 | """ |
| paul@0 | 969 | Start tracking attribute usage for names in the current namespace, |
| paul@0 | 970 | immediately registering the given 'names'. |
| paul@0 | 971 | """ |
| paul@0 | 972 | |
| paul@0 | 973 | path = self.get_namespace_path() |
| paul@0 | 974 | parent = self.trackers[-1] |
| paul@0 | 975 | tracker = BranchTracker() |
| paul@0 | 976 | self.trackers.append(tracker) |
| paul@0 | 977 | |
| paul@0 | 978 | # Record the given names established as new branches. |
| paul@0 | 979 | |
| paul@0 | 980 | tracker.assign_names(names) |
| paul@0 | 981 | |
| paul@0 | 982 | def assign_name(self, name, name_ref): |
| paul@0 | 983 | |
| paul@0 | 984 | "Assign to 'name' the given 'name_ref' in the current namespace." |
| paul@0 | 985 | |
| paul@0 | 986 | name = self.get_name_for_tracking(name) |
| paul@0 | 987 | self.trackers[-1].assign_names([name], [name_ref]) |
| paul@0 | 988 | |
| paul@0 | 989 | def stop_tracking(self): |
| paul@0 | 990 | |
| paul@0 | 991 | """ |
| paul@0 | 992 | Stop tracking attribute usage, recording computed usage for the current |
| paul@0 | 993 | namespace. |
| paul@0 | 994 | """ |
| paul@0 | 995 | |
| paul@0 | 996 | path = self.get_namespace_path() |
| paul@0 | 997 | tracker = self.trackers.pop() |
| paul@0 | 998 | self.record_assignments_for_access(tracker) |
| paul@0 | 999 | |
| paul@0 | 1000 | self.attr_usage[path] = tracker.get_all_usage() |
| paul@0 | 1001 | self.name_initialisers[path] = tracker.get_all_values() |
| paul@0 | 1002 | |
| paul@0 | 1003 | def start_tracking_in_module(self): |
| paul@0 | 1004 | |
| paul@0 | 1005 | "Start tracking attribute usage in the module." |
| paul@0 | 1006 | |
| paul@0 | 1007 | tracker = BranchTracker() |
| paul@0 | 1008 | self.trackers.append(tracker) |
| paul@0 | 1009 | |
| paul@0 | 1010 | def stop_tracking_in_module(self): |
| paul@0 | 1011 | |
| paul@0 | 1012 | "Stop tracking attribute usage in the module." |
| paul@0 | 1013 | |
| paul@0 | 1014 | tracker = self.trackers[0] |
| paul@0 | 1015 | self.record_assignments_for_access(tracker) |
| paul@0 | 1016 | self.attr_usage[self.name] = tracker.get_all_usage() |
| paul@0 | 1017 | self.name_initialisers[self.name] = tracker.get_all_values() |
| paul@0 | 1018 | |
| paul@0 | 1019 | def record_assignments_for_access(self, tracker): |
| paul@0 | 1020 | |
| paul@0 | 1021 | """ |
| paul@0 | 1022 | For the current path, use the given 'tracker' to record assignment |
| paul@0 | 1023 | version information for attribute accesses. |
| paul@0 | 1024 | """ |
| paul@0 | 1025 | |
| paul@0 | 1026 | path = self.get_path_for_access() |
| paul@0 | 1027 | |
| paul@0 | 1028 | if not self.attr_accessor_branches.has_key(path): |
| paul@0 | 1029 | return |
| paul@0 | 1030 | |
| paul@0 | 1031 | init_item(self.attr_accessors, path, dict) |
| paul@0 | 1032 | attr_accessors = self.attr_accessors[path] |
| paul@0 | 1033 | |
| paul@0 | 1034 | # Obtain the branches applying during each access. |
| paul@0 | 1035 | |
| paul@0 | 1036 | for access, all_branches in self.attr_accessor_branches[path].items(): |
| paul@0 | 1037 | name, attrnames = access |
| paul@0 | 1038 | init_item(attr_accessors, access, list) |
| paul@0 | 1039 | |
| paul@0 | 1040 | # Obtain the assignments applying to each branch. |
| paul@0 | 1041 | |
| paul@0 | 1042 | for branches in all_branches: |
| paul@0 | 1043 | positions = tracker.get_assignment_positions_for_branches(name, branches) |
| paul@0 | 1044 | |
| paul@0 | 1045 | # Detect missing name information. |
| paul@0 | 1046 | |
| paul@0 | 1047 | if None in positions: |
| paul@0 | 1048 | globals = self.global_attr_accesses.get(path) |
| paul@0 | 1049 | accesses = globals and globals.get(name) |
| paul@0 | 1050 | if not accesses: |
| paul@0 | 1051 | print >>sys.stderr, "In %s, %s may not be defined when used." % ( |
| paul@0 | 1052 | self.get_namespace_path(), name) |
| paul@0 | 1053 | positions.remove(None) |
| paul@0 | 1054 | |
| paul@0 | 1055 | attr_accessors[access].append(positions) |
| paul@0 | 1056 | |
| paul@0 | 1057 | def record_branches_for_access(self, branches, name, attrnames): |
| paul@0 | 1058 | |
| paul@0 | 1059 | """ |
| paul@0 | 1060 | Record the given 'branches' for an access involving the given 'name' and |
| paul@0 | 1061 | 'attrnames'. |
| paul@0 | 1062 | """ |
| paul@0 | 1063 | |
| paul@0 | 1064 | access = name, attrnames |
| paul@0 | 1065 | path = self.get_path_for_access() |
| paul@0 | 1066 | |
| paul@0 | 1067 | init_item(self.attr_accessor_branches, path, dict) |
| paul@0 | 1068 | attr_accessor_branches = self.attr_accessor_branches[path] |
| paul@0 | 1069 | |
| paul@0 | 1070 | init_item(attr_accessor_branches, access, list) |
| paul@0 | 1071 | attr_accessor_branches[access].append(branches) |
| paul@0 | 1072 | |
| paul@0 | 1073 | def record_access_details(self, name, attrnames, assignment): |
| paul@0 | 1074 | |
| paul@0 | 1075 | """ |
| paul@0 | 1076 | For the given 'name' and 'attrnames', record an access indicating |
| paul@0 | 1077 | whether 'assignment' is occurring. |
| paul@0 | 1078 | |
| paul@0 | 1079 | These details correspond to accesses otherwise recorded by the attribute |
| paul@0 | 1080 | accessor and attribute access dictionaries. |
| paul@0 | 1081 | """ |
| paul@0 | 1082 | |
| paul@0 | 1083 | access = name, attrnames |
| paul@0 | 1084 | path = self.get_path_for_access() |
| paul@0 | 1085 | |
| paul@0 | 1086 | init_item(self.attr_access_modifiers, path, dict) |
| paul@0 | 1087 | init_item(self.attr_access_modifiers[path], access, list) |
| paul@0 | 1088 | |
| paul@0 | 1089 | access_number = len(self.attr_access_modifiers[path][access]) |
| paul@78 | 1090 | self.attr_access_modifiers[path][access].append(assignment and "A" or self.in_invocation and "I" or "_") |
| paul@0 | 1091 | return access_number |
| paul@0 | 1092 | |
| paul@0 | 1093 | def record_global_access_details(self, name, attrnames): |
| paul@0 | 1094 | |
| paul@0 | 1095 | """ |
| paul@0 | 1096 | Record details of a global access via the given 'name' involving the |
| paul@0 | 1097 | indicated 'attrnames'. |
| paul@0 | 1098 | """ |
| paul@0 | 1099 | |
| paul@0 | 1100 | path = self.get_namespace_path() |
| paul@0 | 1101 | |
| paul@0 | 1102 | init_item(self.global_attr_accesses, path, dict) |
| paul@0 | 1103 | init_item(self.global_attr_accesses[path], name, set) |
| paul@0 | 1104 | self.global_attr_accesses[path][name].add(attrnames) |
| paul@0 | 1105 | |
| paul@0 | 1106 | # Namespace modification. |
| paul@0 | 1107 | |
| paul@0 | 1108 | def record_name(self, name): |
| paul@0 | 1109 | |
| paul@0 | 1110 | "Record the use of 'name' in a namespace." |
| paul@0 | 1111 | |
| paul@0 | 1112 | path = self.get_namespace_path() |
| paul@0 | 1113 | init_item(self.names_used, path, set) |
| paul@0 | 1114 | self.names_used[path].add(name) |
| paul@0 | 1115 | |
| paul@12 | 1116 | def set_module(self, name, module_name): |
| paul@0 | 1117 | |
| paul@0 | 1118 | """ |
| paul@12 | 1119 | Set a module in the current namespace using the given 'name' associated |
| paul@12 | 1120 | with the corresponding 'module_name'. |
| paul@0 | 1121 | """ |
| paul@0 | 1122 | |
| paul@0 | 1123 | if name: |
| paul@12 | 1124 | self.set_general_local(name, Reference("<module>", module_name)) |
| paul@0 | 1125 | |
| paul@0 | 1126 | def set_definition(self, name, kind): |
| paul@0 | 1127 | |
| paul@0 | 1128 | """ |
| paul@0 | 1129 | Set the definition having the given 'name' and 'kind'. |
| paul@0 | 1130 | |
| paul@0 | 1131 | Definitions are set in the static namespace hierarchy, but they can also |
| paul@0 | 1132 | be recorded for function locals. |
| paul@0 | 1133 | """ |
| paul@0 | 1134 | |
| paul@0 | 1135 | if self.is_global(name): |
| paul@0 | 1136 | print >>sys.stderr, "In %s, %s is defined as being global." % ( |
| paul@0 | 1137 | self.get_namespace_path(), name) |
| paul@0 | 1138 | |
| paul@0 | 1139 | path = self.get_object_path(name) |
| paul@0 | 1140 | self.set_object(path, kind) |
| paul@0 | 1141 | |
| paul@0 | 1142 | ref = self.get_object(path) |
| paul@0 | 1143 | if ref.get_kind() == "<var>": |
| paul@0 | 1144 | print >>sys.stderr, "In %s, %s is defined more than once." % ( |
| paul@0 | 1145 | self.get_namespace_path(), name) |
| paul@0 | 1146 | |
| paul@0 | 1147 | if not self.is_global(name) and self.in_function: |
| paul@0 | 1148 | self.set_function_local(name, ref) |
| paul@0 | 1149 | |
| paul@0 | 1150 | def set_function_local(self, name, ref=None): |
| paul@0 | 1151 | |
| paul@0 | 1152 | "Set the local with the given 'name' and optional 'ref'." |
| paul@0 | 1153 | |
| paul@0 | 1154 | locals = self.function_locals[self.get_namespace_path()] |
| paul@0 | 1155 | multiple = not ref or locals.has_key(name) and locals[name] != ref |
| paul@0 | 1156 | locals[name] = multiple and Reference("<var>") or ref |
| paul@0 | 1157 | |
| paul@0 | 1158 | def assign_general_local(self, name, name_ref): |
| paul@0 | 1159 | |
| paul@0 | 1160 | """ |
| paul@0 | 1161 | Set for 'name' the given 'name_ref', recording the name for attribute |
| paul@0 | 1162 | usage tracking. |
| paul@0 | 1163 | """ |
| paul@0 | 1164 | |
| paul@0 | 1165 | self.set_general_local(name, name_ref) |
| paul@0 | 1166 | self.assign_name(name, name_ref) |
| paul@0 | 1167 | |
| paul@0 | 1168 | def set_general_local(self, name, value=None): |
| paul@0 | 1169 | |
| paul@0 | 1170 | """ |
| paul@0 | 1171 | Set the 'name' with optional 'value' in any kind of local namespace, |
| paul@0 | 1172 | where the 'value' should be a reference if specified. |
| paul@0 | 1173 | """ |
| paul@0 | 1174 | |
| paul@0 | 1175 | init_value = self.get_initialising_value(value) |
| paul@0 | 1176 | |
| paul@0 | 1177 | # Module global names. |
| paul@0 | 1178 | |
| paul@0 | 1179 | if self.is_global(name): |
| paul@0 | 1180 | path = self.get_global_path(name) |
| paul@0 | 1181 | self.set_object(path, init_value) |
| paul@0 | 1182 | |
| paul@0 | 1183 | # Function local names. |
| paul@0 | 1184 | |
| paul@0 | 1185 | elif self.in_function: |
| paul@0 | 1186 | path = self.get_object_path(name) |
| paul@0 | 1187 | self.set_function_local(name, init_value) |
| paul@0 | 1188 | |
| paul@0 | 1189 | # Other namespaces (classes). |
| paul@0 | 1190 | |
| paul@0 | 1191 | else: |
| paul@0 | 1192 | path = self.get_object_path(name) |
| paul@0 | 1193 | self.set_name(name, init_value) |
| paul@0 | 1194 | |
| paul@0 | 1195 | def set_name(self, name, ref=None): |
| paul@0 | 1196 | |
| paul@0 | 1197 | "Attach the 'name' with optional 'ref' to the current namespace." |
| paul@0 | 1198 | |
| paul@0 | 1199 | self.set_object(self.get_object_path(name), ref) |
| paul@0 | 1200 | |
| paul@0 | 1201 | def set_instance_attr(self, name, ref=None): |
| paul@0 | 1202 | |
| paul@0 | 1203 | """ |
| paul@0 | 1204 | Add an instance attribute of the given 'name' to the current class, |
| paul@0 | 1205 | using the optional 'ref'. |
| paul@0 | 1206 | """ |
| paul@0 | 1207 | |
| paul@0 | 1208 | init_item(self.instance_attrs, self.in_class, set) |
| paul@0 | 1209 | self.instance_attrs[self.in_class].add(name) |
| paul@0 | 1210 | |
| paul@0 | 1211 | if ref: |
| paul@0 | 1212 | init_item(self.instance_attr_constants, self.in_class, dict) |
| paul@0 | 1213 | self.instance_attr_constants[self.in_class][name] = ref |
| paul@0 | 1214 | |
| paul@0 | 1215 | def get_initialising_value(self, value): |
| paul@0 | 1216 | |
| paul@0 | 1217 | "Return a suitable initialiser reference for 'value'." |
| paul@0 | 1218 | |
| paul@25 | 1219 | # Includes LiteralSequenceRef, ResolvedNameRef... |
| paul@25 | 1220 | |
| paul@25 | 1221 | if isinstance(value, (NameRef, AccessRef, InstanceRef)): |
| paul@0 | 1222 | return value.reference() |
| paul@0 | 1223 | |
| paul@0 | 1224 | # In general, invocations do not produce known results. However, the |
| paul@0 | 1225 | # name initialisers are resolved once a module has been inspected. |
| paul@0 | 1226 | |
| paul@0 | 1227 | elif isinstance(value, InvocationRef): |
| paul@27 | 1228 | return value.reference() |
| paul@0 | 1229 | |
| paul@0 | 1230 | else: |
| paul@0 | 1231 | return value |
| paul@0 | 1232 | |
| paul@0 | 1233 | # Static, program-relative naming. |
| paul@0 | 1234 | |
| paul@0 | 1235 | def find_name(self, name): |
| paul@0 | 1236 | |
| paul@0 | 1237 | """ |
| paul@0 | 1238 | Return the qualified name for the given 'name' used in the current |
| paul@0 | 1239 | non-function namespace. |
| paul@0 | 1240 | """ |
| paul@0 | 1241 | |
| paul@0 | 1242 | path = self.get_namespace_path() |
| paul@0 | 1243 | ref = None |
| paul@0 | 1244 | |
| paul@0 | 1245 | if not self.in_function and name not in predefined_constants: |
| paul@0 | 1246 | if self.in_class: |
| paul@0 | 1247 | ref = self.get_object(self.get_object_path(name)) |
| paul@0 | 1248 | if not ref: |
| paul@0 | 1249 | ref = self.get_global_or_builtin(name) |
| paul@0 | 1250 | |
| paul@0 | 1251 | return ref |
| paul@0 | 1252 | |
| paul@0 | 1253 | def get_class(self, node): |
| paul@0 | 1254 | |
| paul@0 | 1255 | """ |
| paul@0 | 1256 | Use the given 'node' to obtain the identity of a class. Return a |
| paul@0 | 1257 | reference for the class. Unresolved dependencies are permitted and must |
| paul@0 | 1258 | be resolved later. |
| paul@0 | 1259 | """ |
| paul@0 | 1260 | |
| paul@0 | 1261 | ref = self._get_class(node) |
| paul@0 | 1262 | return ref.has_kind(["<class>", "<depends>"]) and ref or None |
| paul@0 | 1263 | |
| paul@0 | 1264 | def _get_class(self, node): |
| paul@0 | 1265 | |
| paul@0 | 1266 | """ |
| paul@0 | 1267 | Use the given 'node' to find a class definition. Return a reference to |
| paul@0 | 1268 | the class. |
| paul@0 | 1269 | """ |
| paul@0 | 1270 | |
| paul@0 | 1271 | if isinstance(node, compiler.ast.Getattr): |
| paul@0 | 1272 | |
| paul@0 | 1273 | # Obtain the identity of the access target. |
| paul@0 | 1274 | |
| paul@0 | 1275 | ref = self._get_class(node.expr) |
| paul@0 | 1276 | |
| paul@0 | 1277 | # Where the target is a class or module, obtain the identity of the |
| paul@0 | 1278 | # attribute. |
| paul@0 | 1279 | |
| paul@0 | 1280 | if ref.has_kind(["<function>", "<var>"]): |
| paul@0 | 1281 | return None |
| paul@0 | 1282 | else: |
| paul@0 | 1283 | attrname = "%s.%s" % (ref.get_origin(), node.attrname) |
| paul@0 | 1284 | return self.get_object(attrname) |
| paul@0 | 1285 | |
| paul@0 | 1286 | # Names can be module-level or built-in. |
| paul@0 | 1287 | |
| paul@0 | 1288 | elif isinstance(node, compiler.ast.Name): |
| paul@0 | 1289 | |
| paul@0 | 1290 | # Record usage of the name and attempt to identify it. |
| paul@0 | 1291 | |
| paul@0 | 1292 | self.record_name(node.name) |
| paul@73 | 1293 | return self.find_name(node.name) |
| paul@0 | 1294 | else: |
| paul@0 | 1295 | return None |
| paul@0 | 1296 | |
| paul@0 | 1297 | def get_constant(self, name, value): |
| paul@0 | 1298 | |
| paul@0 | 1299 | "Return a constant reference for the given type 'name' and 'value'." |
| paul@0 | 1300 | |
| paul@12 | 1301 | ref = self.get_builtin_class(name) |
| paul@0 | 1302 | return self.get_constant_reference(ref, value) |
| paul@0 | 1303 | |
| paul@0 | 1304 | def get_literal_instance(self, n, name): |
| paul@0 | 1305 | |
| paul@0 | 1306 | "For node 'n', return a reference to an instance of 'name'." |
| paul@0 | 1307 | |
| paul@12 | 1308 | # Get a reference to the built-in class. |
| paul@0 | 1309 | |
| paul@12 | 1310 | ref = self.get_builtin_class(name) |
| paul@0 | 1311 | |
| paul@0 | 1312 | # Obtain the details of the literal itself. |
| paul@0 | 1313 | # An alias to the type is generated for sequences. |
| paul@0 | 1314 | |
| paul@0 | 1315 | if name in ("dict", "list", "tuple"): |
| paul@0 | 1316 | self.set_special_literal(name, ref) |
| paul@0 | 1317 | return self.process_literal_sequence_node(n, name, ref, LiteralSequenceRef) |
| paul@0 | 1318 | |
| paul@0 | 1319 | # Constant values are independently recorded. |
| paul@0 | 1320 | |
| paul@0 | 1321 | else: |
| paul@0 | 1322 | return self.get_constant_reference(ref, n.value) |
| paul@0 | 1323 | |
| paul@17 | 1324 | # Special names. |
| paul@0 | 1325 | |
| paul@17 | 1326 | def get_special(self, name): |
| paul@0 | 1327 | |
| paul@17 | 1328 | "Return any stored value for the given special 'name'." |
| paul@0 | 1329 | |
| paul@17 | 1330 | return self.special.get(name) |
| paul@17 | 1331 | |
| paul@17 | 1332 | def set_special(self, name, value): |
| paul@0 | 1333 | |
| paul@17 | 1334 | """ |
| paul@17 | 1335 | Set a special 'name' that merely tracks the use of an implicit object |
| paul@17 | 1336 | 'value'. |
| paul@17 | 1337 | """ |
| paul@0 | 1338 | |
| paul@17 | 1339 | self.special[name] = value |
| paul@17 | 1340 | |
| paul@17 | 1341 | def set_special_literal(self, name, ref): |
| paul@0 | 1342 | |
| paul@17 | 1343 | """ |
| paul@17 | 1344 | Set a special name for the literal type 'name' having type 'ref'. Such |
| paul@17 | 1345 | special names provide a way of referring to literal object types. |
| paul@17 | 1346 | """ |
| paul@0 | 1347 | |
| paul@17 | 1348 | literal_name = "$L%s" % name |
| paul@17 | 1349 | value = ResolvedNameRef(literal_name, ref) |
| paul@17 | 1350 | self.set_special(literal_name, value) |
| paul@0 | 1351 | |
| paul@0 | 1352 | # Functions and invocations. |
| paul@0 | 1353 | |
| paul@36 | 1354 | def set_invocation_usage(self): |
| paul@36 | 1355 | |
| paul@36 | 1356 | """ |
| paul@36 | 1357 | Discard the current invocation storage figures, retaining the maximum |
| paul@36 | 1358 | values. |
| paul@36 | 1359 | """ |
| paul@36 | 1360 | |
| paul@36 | 1361 | for path, (current, maximum) in self.function_targets.items(): |
| paul@36 | 1362 | self.importer.function_targets[path] = self.function_targets[path] = maximum |
| paul@36 | 1363 | |
| paul@36 | 1364 | for path, (current, maximum) in self.function_arguments.items(): |
| paul@36 | 1365 | self.importer.function_arguments[path] = self.function_arguments[path] = maximum |
| paul@36 | 1366 | |
| paul@0 | 1367 | def allocate_arguments(self, path, args): |
| paul@0 | 1368 | |
| paul@0 | 1369 | """ |
| paul@0 | 1370 | Allocate temporary argument storage using current and maximum |
| paul@0 | 1371 | requirements for the given 'path' and 'args'. |
| paul@0 | 1372 | """ |
| paul@0 | 1373 | |
| paul@0 | 1374 | init_item(self.function_targets, path, lambda: [0, 0]) |
| paul@0 | 1375 | t = self.function_targets[path] |
| paul@0 | 1376 | t[0] += 1 |
| paul@0 | 1377 | t[1] = max(t[0], t[1]) |
| paul@0 | 1378 | |
| paul@0 | 1379 | init_item(self.function_arguments, path, lambda: [0, 0]) |
| paul@0 | 1380 | t = self.function_arguments[path] |
| paul@0 | 1381 | t[0] += len(args) + 1 |
| paul@0 | 1382 | t[1] = max(t[0], t[1]) |
| paul@0 | 1383 | |
| paul@0 | 1384 | def deallocate_arguments(self, path, args): |
| paul@0 | 1385 | |
| paul@0 | 1386 | "Deallocate temporary argument storage for the given 'path' and 'args'." |
| paul@0 | 1387 | |
| paul@0 | 1388 | self.function_targets[path][0] -= 1 |
| paul@0 | 1389 | self.function_arguments[path][0] -= len(args) + 1 |
| paul@0 | 1390 | |
| paul@0 | 1391 | # vim: tabstop=4 expandtab shiftwidth=4 |
