Commit 0e55d5f3 authored by Dag Sverre Seljebotn's avatar Dag Sverre Seljebotn

Support for parse tree transformations.

parent 3ee07211
......@@ -4,6 +4,7 @@
import sys
import Options
import Transform
usage = """\
Cython (http://cython.org) is a compiler for code written in the
......@@ -36,11 +37,36 @@ Options:
# -+, --cplus Use C++ compiler for compiling and linking
# Additional .o files to link may be supplied when using -X."""
#The following options are very experimental and is used for plugging in code
#into different transform stages.
# -T phase:factory At the phase given, hand off the tree to the transform returned
# when calling factory without arguments. Factory should be fully
# specified (ie Module.SubModule.factory) and the containing module
# will be imported. This option can be repeated to add more transforms,
# transforms for the same phase will be used in the order they are given.
def bad_usage():
print >>sys.stderr, usage
sys.exit(1)
def parse_command_line(args):
def parse_add_transform(transforms, param):
def import_symbol(fqn):
modsplitpt = fqn.rfind(".")
if modsplitpt == -1: bad_usage()
modulename = fqn[:modsplitpt]
symbolname = fqn[modsplitpt+1:]
module = __import__(modulename, fromlist=[symbolname], level=0)
return getattr(module, symbolname)
stagename, factoryname = param.split(":")
if not stagename in Transform.PHASES:
bad_usage()
factory = import_symbol(factoryname)
transform = factory()
transforms[stagename].append(transform)
from Cython.Compiler.Main import \
CompilationOptions, default_options
......@@ -93,6 +119,9 @@ def parse_command_line(args):
Options.annotate = True
elif option == "--convert-range":
Options.convert_range = True
elif option.startswith("-T"):
parse_add_transform(options.transforms, get_param(option))
# Note: this can occur multiple times, each time appends
else:
bad_usage()
else:
......
......@@ -31,6 +31,7 @@ class ExprNode(Node):
# Cached result of subexpr_nodes()
result_ctype = None
type = None
# The Analyse Expressions phase for expressions is split
# into two sub-phases:
......@@ -165,6 +166,14 @@ class ExprNode(Node):
saved_subexpr_nodes = None
is_temp = 0
def get_child_attrs(self):
"""Automatically provide the contents of subexprs as children, unless child_attr
has been declared. See Nodes.Node.get_child_accessors."""
if self.child_attrs != None:
return self.child_attr
elif self.subexprs != None:
return self.subexprs
def not_implemented(self, method_name):
print_call_chain(method_name, "not implemented") ###
raise InternalError(
......
......@@ -18,6 +18,7 @@ from Symtab import BuiltinScope, ModuleScope
import Code
from Cython.Utils import replace_suffix
from Cython import Utils
import Transform
verbose = 0
......@@ -236,6 +237,7 @@ class CompilationOptions:
include_path [string] Directories to search for include files
output_file string Name of generated .c file
generate_pxi boolean Generate .pxi file for public declarations
transforms Transform.TransformSet Transforms to use on the parse tree
Following options are experimental and only used on MacOSX:
......@@ -342,7 +344,8 @@ default_options = dict(
obj_only = 1,
cplus = 0,
output_file = None,
generate_pxi = 0)
generate_pxi = 0,
transforms = Transform.TransformSet())
if sys.platform == "mac":
from Cython.Mac.MacSystem import c_compile, c_link, CCompilerError
......
......@@ -27,6 +27,8 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
# module_temp_cname string
# full_module_name string
children_attrs = ["body"]
def analyse_declarations(self, env):
if Options.embed_pos_in_docstring:
env.doc = 'File: %s (starting at line %s)'%Nodes.relative_position(self.pos)
......@@ -46,7 +48,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
if self.has_imported_c_functions():
self.module_temp_cname = env.allocate_temp_pyobject()
env.release_temp(self.module_temp_cname)
self.generate_c_code(env, result)
self.generate_c_code(env, options, result)
self.generate_h_code(env, options, result)
self.generate_api_code(env, result)
......@@ -199,7 +201,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
i_code.putln("pass")
i_code.dedent()
def generate_c_code(self, env, result):
def generate_c_code(self, env, options, result):
modules = self.referenced_modules
if Options.annotate:
code = Annotate.AnnotationCCodeWriter(StringIO())
......@@ -216,7 +218,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
self.generate_interned_name_decls(env, code)
self.generate_py_string_decls(env, code)
self.generate_cached_builtins_decls(env, code)
self.body.generate_function_definitions(env, code)
self.body.generate_function_definitions(env, code, options.transforms)
code.mark_pos(None)
self.generate_interned_name_table(env, code)
self.generate_py_string_table(env, code)
......
......@@ -38,6 +38,21 @@ def relative_position(pos):
return (pos[0][absolute_path_length+1:], pos[1])
class AttributeAccessor:
"""Used as the result of the Node.get_children_accessors() generator"""
def __init__(self, obj, attrname):
self.obj = obj
self.attrname = attrname
def get(self):
try:
return getattr(self.obj, self.attrname)
except AttributeError:
return None
def set(self, value):
setattr(self.obj, self.attrname, value)
def name(self):
return self.attrname
class Node:
# pos (string, int, int) Source file position
# is_name boolean Is a NameNode
......@@ -46,10 +61,63 @@ class Node:
is_name = 0
is_literal = 0
# All descandants should set child_attrs (see get_child_accessors)
child_attrs = None
def __init__(self, pos, **kw):
self.pos = pos
self.__dict__.update(kw)
def get_child_accessors(self):
"""Returns an iterator over the children of the Node. Each member in the
iterated list is an object with get(), set(value), and name() methods,
which can be used to fetch and replace the child and query the name
the relation this node has with the child. For instance, for an
assignment node, this code:
for child in assignment_node.get_child_accessors():
print(child.name())
child.set(i_node)
will print "lhs", "rhs", and change the assignment statement to "i = i"
(assuming that i_node is a node able to represent the variable i in the
tree).
Any kind of objects can in principle be returned, but the typical
candidates are either Node instances or lists of node instances.
The object returned in each iteration stage can only be used until the
iterator is advanced to the next child attribute. (However, the objects
returned by the get() function can be kept).
Typically, a Node instance will have other interesting and potentially
hierarchical attributes as well. These must be explicitly accessed -- this
method only provides access to attributes that are deemed to naturally
belong in the parse tree.
Descandant classes can either specify child_attrs, override get_child_attrs,
or override this method directly in order to provide access to their
children. All descendants of Node *must* declare their children -- leaf nodes
should simply declare "child_attrs = []".
"""
attrnames = self.get_child_attrs()
if attrnames is None:
raise InternalError("Children access not implemented for %s" % \
self.__class__.__name__)
for name in attrnames:
a = AttributeAccessor(self, name)
yield a
# Not really needed, but one wants to enforce clients not to
# hold on to iterated objects, in case more advanced iteration
# is needed later
a.attrname = None
def get_child_attrs(self):
"""Utility method for more easily implementing get_child_accessors.
If you override get_child_accessors then this method is not used."""
return self.child_attrs
#
# There are 3 phases of parse tree processing, applied in order to
# all the statements in a given scope-block:
......@@ -145,6 +213,8 @@ class BlockNode:
class StatListNode(Node):
# stats a list of StatNode
child_attrs = ["stats"]
def analyse_declarations(self, env):
#print "StatListNode.analyse_declarations" ###
for stat in self.stats:
......@@ -155,10 +225,10 @@ class StatListNode(Node):
for stat in self.stats:
stat.analyse_expressions(env)
def generate_function_definitions(self, env, code):
def generate_function_definitions(self, env, code, transforms):
#print "StatListNode.generate_function_definitions" ###
for stat in self.stats:
stat.generate_function_definitions(env, code)
stat.generate_function_definitions(env, code, transforms)
def generate_execution_code(self, code):
#print "StatListNode.generate_execution_code" ###
......@@ -184,7 +254,7 @@ class StatNode(Node):
# Emit C code for executable statements.
#
def generate_function_definitions(self, env, code):
def generate_function_definitions(self, env, code, transforms):
pass
def generate_execution_code(self, code):
......@@ -196,6 +266,8 @@ class CDefExternNode(StatNode):
# include_file string or None
# body StatNode
child_attrs = ["body"]
def analyse_declarations(self, env):
if self.include_file:
env.add_include_file(self.include_file)
......@@ -227,6 +299,8 @@ class CDeclaratorNode(Node):
# calling_convention string Calling convention of CFuncDeclaratorNode
# for which this is a base
child_attrs = []
calling_convention = ""
def analyse_expressions(self, env):
......@@ -240,6 +314,8 @@ class CNameDeclaratorNode(CDeclaratorNode):
# name string The Pyrex name being declared
# cname string or None C name, if specified
child_attrs = []
def analyse(self, base_type, env):
self.type = base_type
return self, base_type
......@@ -268,6 +344,8 @@ class CNameDeclaratorNode(CDeclaratorNode):
class CPtrDeclaratorNode(CDeclaratorNode):
# base CDeclaratorNode
child_attrs = ["base"]
def analyse(self, base_type, env):
if base_type.is_pyobject:
error(self.pos,
......@@ -285,6 +363,8 @@ class CArrayDeclaratorNode(CDeclaratorNode):
# base CDeclaratorNode
# dimension ExprNode
child_attrs = ["base", "dimension"]
def analyse(self, base_type, env):
if self.dimension:
self.dimension.analyse_const_expression(env)
......@@ -315,6 +395,8 @@ class CFuncDeclaratorNode(CDeclaratorNode):
# nogil boolean Can be called without gil
# with_gil boolean Acquire gil around function body
child_attrs = ["base", "args", "exception_value"]
overridable = 0
optional_arg_count = 0
......@@ -403,6 +485,8 @@ class CArgDeclNode(Node):
# is_self_arg boolean Is the "self" arg of an extension type method
# is_kw_only boolean Is a keyword-only argument
child_attrs = ["base_type", "declarator", "default"]
is_self_arg = 0
is_generic = 1
......@@ -435,6 +519,8 @@ class CSimpleBaseTypeNode(CBaseTypeNode):
# longness integer
# is_self_arg boolean Is self argument of C method
child_attrs = []
def analyse(self, env):
# Return type descriptor.
#print "CSimpleBaseTypeNode.analyse: is_self_arg =", self.is_self_arg ###
......@@ -480,6 +566,8 @@ class CComplexBaseTypeNode(CBaseTypeNode):
# base_type CBaseTypeNode
# declarator CDeclaratorNode
child_attrs = ["base_type", "declarator"]
def analyse(self, env):
base = self.base_type.analyse(env)
_, type = self.declarator.analyse(base, env)
......@@ -495,6 +583,8 @@ class CVarDefNode(StatNode):
# in_pxd boolean
# api boolean
child_attrs = ["base_type", "declarators"]
def analyse_declarations(self, env, dest_scope = None):
if not dest_scope:
dest_scope = env
......@@ -543,6 +633,8 @@ class CStructOrUnionDefNode(StatNode):
# attributes [CVarDefNode] or None
# entry Entry
child_attrs = ["attributes"]
def analyse_declarations(self, env):
scope = None
if self.attributes is not None:
......@@ -572,6 +664,8 @@ class CEnumDefNode(StatNode):
# in_pxd boolean
# entry Entry
child_attrs = ["items"]
def analyse_declarations(self, env):
self.entry = env.declare_enum(self.name, self.pos,
cname = self.cname, typedef_flag = self.typedef_flag,
......@@ -594,6 +688,8 @@ class CEnumDefItemNode(StatNode):
# cname string or None
# value ExprNode or None
child_attrs = ["value"]
def analyse_declarations(self, env, enum_entry):
if self.value:
self.value.analyse_const_expression(env)
......@@ -611,6 +707,8 @@ class CTypeDefNode(StatNode):
# visibility "public" or "private"
# in_pxd boolean
child_attrs = ["base_type", "declarator"]
def analyse_declarations(self, env):
base = self.base_type.analyse(env)
name_declarator, type = self.declarator.analyse(base, env)
......@@ -663,7 +761,7 @@ class FuncDefNode(StatNode, BlockNode):
def need_gil_acquisition(self, lenv):
return 0
def generate_function_definitions(self, env, code):
def generate_function_definitions(self, env, code, transforms):
code.mark_pos(self.pos)
# Generate C code for header and body of function
genv = env.global_scope()
......@@ -671,8 +769,10 @@ class FuncDefNode(StatNode, BlockNode):
lenv.return_type = self.return_type
code.init_labels()
self.declare_arguments(lenv)
transforms.run('before_analyse_function', self, env=env, lenv=lenv, genv=genv)
self.body.analyse_declarations(lenv)
self.body.analyse_expressions(lenv)
transforms.run('after_analyse_function', self, env=env, lenv=lenv, genv=genv)
# Code for nested function definitions would go here
# if we supported them, which we probably won't.
# ----- Top-level constants used by this function
......@@ -775,7 +875,7 @@ class FuncDefNode(StatNode, BlockNode):
code.putln("}")
# ----- Python version
if self.py_func:
self.py_func.generate_function_definitions(env, code)
self.py_func.generate_function_definitions(env, code, transforms)
self.generate_optarg_wrapper_function(env, code)
def put_stararg_decrefs(self, code):
......@@ -834,6 +934,8 @@ class CFuncDefNode(FuncDefNode):
# with_gil boolean Acquire GIL around body
# type CFuncType
child_attrs = ["base_type", "declarator", "body"]
def unqualified_name(self):
return self.entry.name
......@@ -1032,6 +1134,7 @@ class PyArgDeclNode(Node):
#
# name string
# entry Symtab.Entry
child_attrs = []
pass
......@@ -1051,6 +1154,8 @@ class DefNode(FuncDefNode):
#
# assmt AssignmentNode Function construction/assignment
child_attrs = ["args", "star_arg", "starstar_arg", "body"]
assmt = None
num_kwonly_args = 0
num_required_kw_args = 0
......@@ -1740,6 +1845,8 @@ class PyClassDefNode(StatNode, BlockNode):
# classobj ClassNode Class object
# target NameNode Variable to assign class object to
child_attrs = ["body", "dict", "classobj", "target"]
def __init__(self, pos, name, bases, doc, body):
StatNode.__init__(self, pos)
self.name = name
......@@ -1777,10 +1884,10 @@ class PyClassDefNode(StatNode, BlockNode):
#self.classobj.release_temp(env)
#self.target.release_target_temp(env)
def generate_function_definitions(self, env, code):
def generate_function_definitions(self, env, code, transforms):
self.generate_py_string_decls(self.scope, code)
self.body.generate_function_definitions(
self.scope, code)
self.scope, code, transforms)
def generate_execution_code(self, code):
self.dict.generate_evaluation_code(code)
......@@ -1809,6 +1916,8 @@ class CClassDefNode(StatNode):
# entry Symtab.Entry
# base_type PyExtensionType or None
child_attrs = ["body"]
def analyse_declarations(self, env):
#print "CClassDefNode.analyse_declarations:", self.class_name
#print "...visibility =", self.visibility
......@@ -1880,10 +1989,10 @@ class CClassDefNode(StatNode):
scope = self.entry.type.scope
self.body.analyse_expressions(scope)
def generate_function_definitions(self, env, code):
def generate_function_definitions(self, env, code, transforms):
if self.body:
self.body.generate_function_definitions(
self.entry.type.scope, code)
self.entry.type.scope, code, transforms)
def generate_execution_code(self, code):
# This is needed to generate evaluation code for
......@@ -1903,6 +2012,8 @@ class PropertyNode(StatNode):
# doc string or None Doc string
# body StatListNode
child_attrs = ["body"]
def analyse_declarations(self, env):
entry = env.declare_property(self.name, self.doc, self.pos)
if entry:
......@@ -1914,8 +2025,8 @@ class PropertyNode(StatNode):
def analyse_expressions(self, env):
self.body.analyse_expressions(env)
def generate_function_definitions(self, env, code):
self.body.generate_function_definitions(env, code)
def generate_function_definitions(self, env, code, transforms):
self.body.generate_function_definitions(env, code, transforms)
def generate_execution_code(self, code):
pass
......@@ -1929,6 +2040,8 @@ class GlobalNode(StatNode):
#
# names [string]
child_attrs = []
def analyse_declarations(self, env):
for name in self.names:
env.declare_global(name, self.pos)
......@@ -1945,6 +2058,8 @@ class ExprStatNode(StatNode):
#
# expr ExprNode
child_attrs = ["expr"]
def analyse_expressions(self, env):
self.expr.analyse_expressions(env)
self.expr.release_temp(env)
......@@ -1990,6 +2105,8 @@ class SingleAssignmentNode(AssignmentNode):
# lhs ExprNode Left hand side
# rhs ExprNode Right hand side
child_attrs = ["lhs", "rhs"]
def analyse_declarations(self, env):
self.lhs.analyse_target_declaration(env)
......@@ -2044,6 +2161,8 @@ class CascadedAssignmentNode(AssignmentNode):
#
# coerced_rhs_list [ExprNode] RHS coerced to type of each LHS
child_attrs = ["lhs_list", "rhs", "coerced_rhs_list"]
def analyse_declarations(self, env):
for lhs in self.lhs_list:
lhs.analyse_target_declaration(env)
......@@ -2128,6 +2247,8 @@ class ParallelAssignmentNode(AssignmentNode):
#
# stats [AssignmentNode] The constituent assignments
child_attrs = ["stats"]
def analyse_declarations(self, env):
for stat in self.stats:
stat.analyse_declarations(env)
......@@ -2175,6 +2296,8 @@ class InPlaceAssignmentNode(AssignmentNode):
# Fortunately, the type of the lhs node is fairly constrained
# (it must be a NameNode, AttributeNode, or IndexNode).
child_attrs = ["lhs", "rhs", "dup"]
def analyse_declarations(self, env):
self.lhs.analyse_target_declaration(env)
......@@ -2272,6 +2395,8 @@ class PrintStatNode(StatNode):
# args [ExprNode]
# ends_with_comma boolean
child_attrs = ["args"]
def analyse_expressions(self, env):
for i in range(len(self.args)):
arg = self.args[i]
......@@ -2306,6 +2431,8 @@ class DelStatNode(StatNode):
#
# args [ExprNode]
child_attrs = ["args"]
def analyse_declarations(self, env):
for arg in self.args:
arg.analyse_target_declaration(env)
......@@ -2331,6 +2458,8 @@ class DelStatNode(StatNode):
class PassStatNode(StatNode):
# pass statement
child_attrs = []
def analyse_expressions(self, env):
pass
......@@ -2340,6 +2469,8 @@ class PassStatNode(StatNode):
class BreakStatNode(StatNode):
child_attrs = []
def analyse_expressions(self, env):
pass
......@@ -2355,6 +2486,8 @@ class BreakStatNode(StatNode):
class ContinueStatNode(StatNode):
child_attrs = []
def analyse_expressions(self, env):
pass
......@@ -2377,6 +2510,8 @@ class ReturnStatNode(StatNode):
# return_type PyrexType
# temps_in_use [Entry] Temps in use at time of return
child_attrs = ["value"]
def analyse_expressions(self, env):
return_type = env.return_type
self.return_type = return_type
......@@ -2439,6 +2574,8 @@ class RaiseStatNode(StatNode):
# exc_value ExprNode or None
# exc_tb ExprNode or None
child_attrs = ["exc_type", "exc_value", "exc_tb"]
def analyse_expressions(self, env):
if self.exc_type:
self.exc_type.analyse_types(env)
......@@ -2508,6 +2645,8 @@ class RaiseStatNode(StatNode):
class ReraiseStatNode(StatNode):
child_attrs = []
def analyse_expressions(self, env):
env.use_utility_code(raise_utility_code)
......@@ -2526,6 +2665,8 @@ class AssertStatNode(StatNode):
# cond ExprNode
# value ExprNode or None
child_attrs = ["cond", "value"]
def analyse_expressions(self, env):
self.cond = self.cond.analyse_boolean_expression(env)
if self.value:
......@@ -2571,6 +2712,8 @@ class IfStatNode(StatNode):
# if_clauses [IfClauseNode]
# else_clause StatNode or None
child_attrs = ["if_clauses", "else_clause"]
def analyse_declarations(self, env):
for if_clause in self.if_clauses:
if_clause.analyse_declarations(env)
......@@ -2607,6 +2750,8 @@ class IfClauseNode(Node):
# condition ExprNode
# body StatNode
child_attrs = ["condition", "body"]
def analyse_declarations(self, env):
self.condition.analyse_declarations(env)
self.body.analyse_declarations(env)
......@@ -2642,6 +2787,8 @@ class WhileStatNode(StatNode):
# body StatNode
# else_clause StatNode
child_attrs = ["condition", "body", "else_clause"]
def analyse_declarations(self, env):
self.body.analyse_declarations(env)
if self.else_clause:
......@@ -2697,6 +2844,8 @@ class ForInStatNode(StatNode):
# else_clause StatNode
# item NextNode used internally
child_attrs = ["target", "iterator", "body", "else_clause", "item"]
def analyse_declarations(self, env):
self.target.analyse_target_declaration(env)
self.body.analyse_declarations(env)
......@@ -2811,6 +2960,7 @@ class ForFromStatNode(StatNode):
# is_py_target bool
# loopvar_name string
# py_loopvar_node PyTempNode or None
child_attrs = ["target", "bound1", "bound2", "step", "body", "else_clause", "py_loopvar_node"]
def analyse_declarations(self, env):
self.target.analyse_target_declaration(env)
......@@ -2934,6 +3084,8 @@ class TryExceptStatNode(StatNode):
# else_clause StatNode or None
# cleanup_list [Entry] temps to clean up on error
child_attrs = ["body", "except_clauses", "else_clause", "cleanup_list"]
def analyse_declarations(self, env):
self.body.analyse_declarations(env)
for except_clause in self.except_clauses:
......@@ -2999,6 +3151,8 @@ class ExceptClauseNode(Node):
# function_name string qualified name of enclosing function
# exc_vars (string * 3) local exception variables
child_attrs = ["pattern", "target", "body", "exc_value"]
def analyse_declarations(self, env):
if self.target:
self.target.analyse_target_declaration(env)
......@@ -3085,6 +3239,8 @@ class TryFinallyStatNode(StatNode):
# exception on entry to the finally block and restore
# it on exit.
child_attrs = ["body", "finally_clause", "cleanup_list"]
preserve_exception = 1
disallow_continue_in_try_finally = 0
......@@ -3243,6 +3399,8 @@ class GILStatNode(TryFinallyStatNode):
#
# state string 'gil' or 'nogil'
child_attrs = []
preserve_exception = 0
def __init__(self, pos, state, body):
......@@ -3280,6 +3438,8 @@ class GILExitNode(StatNode):
#
# state string 'gil' or 'nogil'
child_attrs = []
def analyse_expressions(self, env):
pass
......@@ -3296,6 +3456,8 @@ class CImportStatNode(StatNode):
# module_name string Qualified name of module being imported
# as_name string or None Name specified in "as" clause, if any
child_attrs = []
def analyse_declarations(self, env):
if not env.is_module_scope:
error(self.pos, "cimport only allowed at module level")
......@@ -3331,6 +3493,8 @@ class FromCImportStatNode(StatNode):
# module_name string Qualified name of module
# imported_names [(pos, name, as_name)] Names to be imported
child_attrs = []
def analyse_declarations(self, env):
if not env.is_module_scope:
error(self.pos, "cimport only allowed at module level")
......@@ -3358,6 +3522,8 @@ class FromImportStatNode(StatNode):
# interned_items [(string, NameNode)]
# item PyTempNode used internally
child_attrs = ["module"]
def analyse_declarations(self, env):
for _, target in self.items:
target.analyse_target_declaration(env)
......
#
# Tree transform framework
#
import Nodes
import ExprNodes
class Transform(object):
# parent_stack [Node] A stack providing information about where in the tree
# we currently are. Nodes here should be considered
# read-only.
# Transforms for the parse tree should usually extend this class for convenience.
# The caller of a transform will only first call initialize and then process_node on
# the root node, the rest are utility functions and conventions.
# Transformations usually happens by recursively filtering through the stream.
# process_node is always expected to return a new node, however it is ok to simply
# return the input node untouched. Returning None will remove the node from the
# parent.
def __init__(self):
self.parent_stack = []
def initialize(self, phase, **options):
pass
def process_children(self, node):
"""For all children of node, either process_list (if isinstance(node, list))
or process_node (otherwise) is called."""
if node == None: return
self.parent_stack.append(node)
for childacc in node.get_child_accessors():
child = childacc.get()
if isinstance(child, list):
newchild = self.process_list(child, childacc.name())
if not isinstance(newchild, list): raise Exception("Cannot replace list with non-list!")
else:
newchild = self.process_node(child, childacc.name())
if newchild is not None and not isinstance(newchild, Nodes.Node):
raise Exception("Cannot replace Node with non-Node!")
childacc.set(newchild)
self.parent_stack.pop()
def process_list(self, l, name):
"""Calls process_node on all the items in l, using the name one gets when appending
[idx] to the name. Each item in l is transformed in-place by the item process_node
returns, then l is returned."""
# Comment: If moving to a copying strategy, it might makes sense to return a
# new list instead.
for idx in xrange(len(l)):
l[idx] = self.process_node(l[idx], "%s[%d]" % (name, idx))
return l
def process_node(self, node, name):
"""Override this method to process nodes. name specifies which kind of relation the
parent has with child. This method should always return the node which the parent
should use for this relation, which can either be the same node, None to remove
the node, or a different node."""
raise InternalError("Not implemented")
class PrintTree(Transform):
"""Prints a representation of the tree to standard output.
Subclass and override repr_of to provide more information
about nodes. """
def __init__(self):
Transform.__init__(self)
self._indent = ""
def indent(self):
self._indent += " "
def unindent(self):
self._indent = self._indent[:-2]
def initialize(self, phase, **options):
print("Parse tree dump at phase '%s'" % phase)
# Don't do anything about process_list, the defaults gives
# nice-looking name[idx] nodes which will visually appear
# under the parent-node, not displaying the list itself in
# the hierarchy.
def process_node(self, node, name):
print("%s- %s: %s" % (self._indent, name, self.repr_of(node)))
self.indent()
self.process_children(node)
self.unindent()
return node
def repr_of(self, node):
if node is None:
return "(none)"
else:
result = node.__class__.__name__
if isinstance(node, ExprNodes.ExprNode):
t = node.type
result += "(type=%s)" % repr(t)
return result
PHASES = [
'before_analyse_function', # run in FuncDefNode.generate_function_definitions
'after_analyse_function' # run in FuncDefNode.generate_function_definitions
]
class TransformSet(dict):
def __init__(self):
self.update([(name, []) for name in PHASES])
def run(self, name, node, **options):
assert name in self
for transform in self[name]:
transform.initialize(phase=name, **options)
transform.process_node(node, "(root)")
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment