diff options
Diffstat (limited to 'Demo/parser/example.py')
| -rw-r--r-- | Demo/parser/example.py | 133 |
1 files changed, 82 insertions, 51 deletions
diff --git a/Demo/parser/example.py b/Demo/parser/example.py index c428aff1e8..363f5bb693 100644 --- a/Demo/parser/example.py +++ b/Demo/parser/example.py @@ -1,6 +1,8 @@ """Simple code to extract class & function docstrings from a module. - +This code is used as an example in the library reference manual in the +section on using the parser module. Refer to the manual for a thorough +discussion of the operation of this code. """ import symbol @@ -23,12 +25,35 @@ def get_docs(fileName): return ModuleInfo(tup, basename) -class DefnInfo: +class SuiteInfoBase: _docstring = '' _name = '' - def __init__(self, tree): - self._name = tree[2][1] + def __init__(self, tree = None): + self._class_info = {} + self._function_info = {} + if tree: + self._extract_info(tree) + + def _extract_info(self, tree): + # extract docstring + if len(tree) == 2: + found, vars = match(DOCSTRING_STMT_PATTERN[1], tree[1]) + else: + found, vars = match(DOCSTRING_STMT_PATTERN, tree[3]) + if found: + self._docstring = eval(vars['docstring']) + # discover inner definitions + for node in tree[1:]: + found, vars = match(COMPOUND_STMT_PATTERN, node) + if found: + cstmt = vars['compound'] + if cstmt[0] == symbol.funcdef: + name = cstmt[2][1] + self._function_info[name] = FunctionInfo(cstmt) + elif cstmt[0] == symbol.classdef: + name = cstmt[2][1] + self._class_info[name] = ClassInfo(cstmt) def get_docstring(self): return self._docstring @@ -36,38 +61,21 @@ class DefnInfo: def get_name(self): return self._name -class SuiteInfoBase(DefnInfo): - def __init__(self): - self._class_info = {} - self._function_info = {} - def get_class_names(self): return self._class_info.keys() def get_class_info(self, name): return self._class_info[name] - def _extract_info(self, tree): - if len(tree) >= 4: - found, vars = match(DOCSTRING_STMT_PATTERN, tree[3]) - if found: - self._docstring = eval(vars['docstring']) - for node in tree[1:]: - if (node[0] == symbol.stmt - and node[1][0] == symbol.compound_stmt): - if node[1][1][0] == symbol.funcdef: - name = node[1][1][2][1] - self._function_info[name] = \ - FunctionInfo(node[1][1]) - elif node[1][1][0] == symbol.classdef: - name = node[1][1][2][1] - self._class_info[name] = ClassInfo(node[1][1]) - - -class SuiteInfo(SuiteInfoBase): - def __init__(self, tree): - SuiteInfoBase.__init__(self) - self._extract_info(tree) + def __getitem__(self, name): + try: + return self._class_info[name] + except KeyError: + return self._function_info[name] + + +class SuiteFuncInfo: + # Mixin class providing access to function names and info. def get_function_names(self): return self._function_info.keys() @@ -76,23 +84,16 @@ class SuiteInfo(SuiteInfoBase): return self._function_info[name] -class FunctionInfo(SuiteInfo): - def __init__(self, tree): - DefnInfo.__init__(self, tree) - suite = tree[-1] - if len(suite) >= 4: - found, vars = match(DOCSTRING_STMT_PATTERN, suite[3]) - if found: - self._docstring = eval(vars['docstring']) - SuiteInfoBase.__init__(self) - self._extract_info(suite) +class FunctionInfo(SuiteInfoBase, SuiteFuncInfo): + def __init__(self, tree = None): + self._name = tree[2][1] + SuiteInfoBase.__init__(self, tree and tree[-1] or None) class ClassInfo(SuiteInfoBase): - def __init__(self, tree): - SuiteInfoBase.__init__(self) - DefnInfo.__init__(self, tree) - self._extract_info(tree[-1]) + def __init__(self, tree = None): + self._name = tree[2][1] + SuiteInfoBase.__init__(self, tree and tree[-1] or None) def get_method_names(self): return self._function_info.keys() @@ -101,19 +102,40 @@ class ClassInfo(SuiteInfoBase): return self._function_info[name] -class ModuleInfo(SuiteInfo): - def __init__(self, tree, name="<string>"): +class ModuleInfo(SuiteInfoBase, SuiteFuncInfo): + def __init__(self, tree = None, name = "<string>"): self._name = name - SuiteInfo.__init__(self, tree) - found, vars = match(DOCSTRING_STMT_PATTERN, tree[1]) - if found: - self._docstring = vars["docstring"] + SuiteInfoBase.__init__(self, tree) + if tree: + found, vars = match(DOCSTRING_STMT_PATTERN, tree[1]) + if found: + self._docstring = vars["docstring"] from types import ListType, TupleType def match(pattern, data, vars=None): - """ + """Match `data' to `pattern', with variable extraction. + + pattern + Pattern to match against, possibly containing variables. + + data + Data to be checked and against which variables are extracted. + + vars + Dictionary of variables which have already been found. If not + provided, an empty dictionary is created. + + The `pattern' value may contain variables of the form ['varname'] which + are allowed to match anything. The value that is matched is returned as + part of a dictionary which maps 'varname' to the matched value. 'varname' + is not required to be a string object, but using strings makes patterns + and the code which uses them more readable. + + This function returns two values: a boolean indicating whether a match + was found and a dictionary mapping variable names to their associated + values. """ if vars is None: vars = {} @@ -131,6 +153,15 @@ def match(pattern, data, vars=None): return same, vars +# This pattern identifies compound statements, allowing them to be readily +# differentiated from simple statements. +# +COMPOUND_STMT_PATTERN = ( + symbol.stmt, + (symbol.compound_stmt, ['compound']) + ) + + # This pattern will match a 'stmt' node which *might* represent a docstring; # docstrings require that the statement which provides the docstring be the # first statement in the class or function, which this pattern does not check. |