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-rw-r--r--Demo/parser/unparse.py316
1 files changed, 158 insertions, 158 deletions
diff --git a/Demo/parser/unparse.py b/Demo/parser/unparse.py
index 2455885..53b57b3 100644
--- a/Demo/parser/unparse.py
+++ b/Demo/parser/unparse.py
@@ -1,158 +1,158 @@
-"Usage: unparse.py <path to source file>"
-import sys
-
-class Unparser:
- """Methods in this class recursively traverse an AST and
- output source code for the abstract syntax; original formatting
- is disregarged. """
-
- def __init__(self, tree, file = sys.stdout):
- """Unparser(tree, file=sys.stdout) -> None.
- Print the source for tree to file."""
- self.f = file
- self._indent = 0
- self.dispatch(tree)
- self.f.flush()
-
- def fill(self, text = ""):
- "Indent a piece of text, according to the current indentation level"
- self.f.write("\n"+" "*self._indent + text)
-
- def write(self, text):
- "Append a piece of text to the current line."
- self.f.write(text)
-
- def enter(self):
- "Print ':', and increase the indentation."
- self.write(":")
- self._indent += 1
-
- def leave(self):
- "Decrease the indentation level."
- self._indent -= 1
-
- def dispatch(self, tree):
- "Dispatcher function, dispatching tree type T to method _T."
- if isinstance(tree, list):
- for t in tree:
- self.dispatch(t)
- return
- meth = getattr(self, "_"+tree.__class__.__name__)
- meth(tree)
-
-
- ############### Unparsing methods ######################
- # There should be one method per concrete grammar type #
- # Constructors should be grouped by sum type. Ideally, #
- # this would follow the order in the grammar, but #
- # currently doesn't. #
- ########################################################
-
- def _Module(self, tree):
- for stmt in tree.body:
- self.dispatch(stmt)
-
- # stmt
- def _Expr(self, tree):
- self.fill()
- self.dispatch(tree.value)
-
- def _Import(self, t):
- self.fill("import ")
- first = True
- for a in t.names:
- if first:
- first = False
- else:
- self.write(", ")
- self.write(a.name)
- if a.asname:
- self.write(" as "+a.asname)
-
- def _Assign(self, t):
- self.fill()
- for target in t.targets:
- self.dispatch(target)
- self.write(" = ")
- self.dispatch(t.value)
-
- def _ClassDef(self, t):
- self.write("\n")
- self.fill("class "+t.name)
- if t.bases:
- self.write("(")
- for a in t.bases:
- self.dispatch(a)
- self.write(", ")
- self.write(")")
- self.enter()
- self.dispatch(t.body)
- self.leave()
-
- def _FunctionDef(self, t):
- self.write("\n")
- self.fill("def "+t.name + "(")
- self.dispatch(t.args)
- self.enter()
- self.dispatch(t.body)
- self.leave()
-
- def _If(self, t):
- self.fill("if ")
- self.dispatch(t.test)
- self.enter()
- # XXX elif?
- self.dispatch(t.body)
- self.leave()
- if t.orelse:
- self.fill("else")
- self.enter()
- self.dispatch(t.orelse)
- self.leave()
-
- # expr
- def _Str(self, tree):
- self.write(repr(tree.s))
-
- def _Name(self, t):
- self.write(t.id)
-
- def _List(self, t):
- self.write("[")
- for e in t.elts:
- self.dispatch(e)
- self.write(", ")
- self.write("]")
-
- unop = {"Invert":"~", "Not": "not", "UAdd":"+", "USub":"-"}
- def _UnaryOp(self, t):
- self.write(self.unop[t.op.__class__.__name__])
- self.write("(")
- self.dispatch(t.operand)
- self.write(")")
-
- # others
- def _arguments(self, t):
- first = True
- # XXX t.defaults
- for a in t.args:
- if first:first = False
- else: self.write(", ")
- self.dispatch(a)
- if t.vararg:
- if first:first = False
- else: self.write(", ")
- self.write("*"+t.vararg)
- if t.kwarg:
- if first:first = False
- else: self.write(", ")
- self.write("**"+self.kwarg)
- self.write(")")
-
-def roundtrip(filename):
- source = open(filename).read()
- tree = compile(source, filename, "exec", 0x400)
- Unparser(tree)
-
-if __name__=='__main__':
- roundtrip(sys.argv[1])
+"Usage: unparse.py <path to source file>"
+import sys
+
+class Unparser:
+ """Methods in this class recursively traverse an AST and
+ output source code for the abstract syntax; original formatting
+ is disregarged. """
+
+ def __init__(self, tree, file = sys.stdout):
+ """Unparser(tree, file=sys.stdout) -> None.
+ Print the source for tree to file."""
+ self.f = file
+ self._indent = 0
+ self.dispatch(tree)
+ self.f.flush()
+
+ def fill(self, text = ""):
+ "Indent a piece of text, according to the current indentation level"
+ self.f.write("\n"+" "*self._indent + text)
+
+ def write(self, text):
+ "Append a piece of text to the current line."
+ self.f.write(text)
+
+ def enter(self):
+ "Print ':', and increase the indentation."
+ self.write(":")
+ self._indent += 1
+
+ def leave(self):
+ "Decrease the indentation level."
+ self._indent -= 1
+
+ def dispatch(self, tree):
+ "Dispatcher function, dispatching tree type T to method _T."
+ if isinstance(tree, list):
+ for t in tree:
+ self.dispatch(t)
+ return
+ meth = getattr(self, "_"+tree.__class__.__name__)
+ meth(tree)
+
+
+ ############### Unparsing methods ######################
+ # There should be one method per concrete grammar type #
+ # Constructors should be grouped by sum type. Ideally, #
+ # this would follow the order in the grammar, but #
+ # currently doesn't. #
+ ########################################################
+
+ def _Module(self, tree):
+ for stmt in tree.body:
+ self.dispatch(stmt)
+
+ # stmt
+ def _Expr(self, tree):
+ self.fill()
+ self.dispatch(tree.value)
+
+ def _Import(self, t):
+ self.fill("import ")
+ first = True
+ for a in t.names:
+ if first:
+ first = False
+ else:
+ self.write(", ")
+ self.write(a.name)
+ if a.asname:
+ self.write(" as "+a.asname)
+
+ def _Assign(self, t):
+ self.fill()
+ for target in t.targets:
+ self.dispatch(target)
+ self.write(" = ")
+ self.dispatch(t.value)
+
+ def _ClassDef(self, t):
+ self.write("\n")
+ self.fill("class "+t.name)
+ if t.bases:
+ self.write("(")
+ for a in t.bases:
+ self.dispatch(a)
+ self.write(", ")
+ self.write(")")
+ self.enter()
+ self.dispatch(t.body)
+ self.leave()
+
+ def _FunctionDef(self, t):
+ self.write("\n")
+ self.fill("def "+t.name + "(")
+ self.dispatch(t.args)
+ self.enter()
+ self.dispatch(t.body)
+ self.leave()
+
+ def _If(self, t):
+ self.fill("if ")
+ self.dispatch(t.test)
+ self.enter()
+ # XXX elif?
+ self.dispatch(t.body)
+ self.leave()
+ if t.orelse:
+ self.fill("else")
+ self.enter()
+ self.dispatch(t.orelse)
+ self.leave()
+
+ # expr
+ def _Str(self, tree):
+ self.write(repr(tree.s))
+
+ def _Name(self, t):
+ self.write(t.id)
+
+ def _List(self, t):
+ self.write("[")
+ for e in t.elts:
+ self.dispatch(e)
+ self.write(", ")
+ self.write("]")
+
+ unop = {"Invert":"~", "Not": "not", "UAdd":"+", "USub":"-"}
+ def _UnaryOp(self, t):
+ self.write(self.unop[t.op.__class__.__name__])
+ self.write("(")
+ self.dispatch(t.operand)
+ self.write(")")
+
+ # others
+ def _arguments(self, t):
+ first = True
+ # XXX t.defaults
+ for a in t.args:
+ if first:first = False
+ else: self.write(", ")
+ self.dispatch(a)
+ if t.vararg:
+ if first:first = False
+ else: self.write(", ")
+ self.write("*"+t.vararg)
+ if t.kwarg:
+ if first:first = False
+ else: self.write(", ")
+ self.write("**"+self.kwarg)
+ self.write(")")
+
+def roundtrip(filename):
+ source = open(filename).read()
+ tree = compile(source, filename, "exec", 0x400)
+ Unparser(tree)
+
+if __name__=='__main__':
+ roundtrip(sys.argv[1])
generated by cgit v0.12 at 2024-11-21 16:34:27 (GMT)