Update Demo/parser/unparse.py to current Python 3.x syntax. Additions:
- relative imports
- keyword-only arguments
- function annotations
- class decorators
- raise ... from ...
- except ... as ...
- nonlocal
- bytes literals
- set literals
- set comprehensions
- dict comprehensions
Removals:
- print statement.
Some of this should be backported to 2.x.
diff --git a/Demo/parser/unparse.py b/Demo/parser/unparse.py
index 0d62e54..715f98b 100644
--- a/Demo/parser/unparse.py
+++ b/Demo/parser/unparse.py
@@ -1,6 +1,6 @@
"Usage: unparse.py <path to source file>"
import sys
-import _ast
+import ast
import io
import os
@@ -20,7 +20,7 @@
class Unparser:
"""Methods in this class recursively traverse an AST and
output source code for the abstract syntax; original formatting
- is disregarged. """
+ is disregarded. """
def __init__(self, tree, file = sys.stdout):
"""Unparser(tree, file=sys.stdout) -> None.
@@ -80,10 +80,11 @@
def _ImportFrom(self, t):
self.fill("from ")
- self.write(t.module)
+ self.write("." * t.level)
+ if t.module:
+ self.write(t.module)
self.write(" import ")
interleave(lambda: self.write(", "), self.dispatch, t.names)
- # XXX(jpe) what is level for?
def _Assign(self, t):
self.fill()
@@ -124,24 +125,14 @@
self.write(", ")
self.dispatch(t.msg)
- def _Print(self, t):
- self.fill("print ")
- do_comma = False
- if t.dest:
- self.write(">>")
- self.dispatch(t.dest)
- do_comma = True
- for e in t.values:
- if do_comma:self.write(", ")
- else:do_comma=True
- self.dispatch(e)
- if not t.nl:
- self.write(",")
-
def _Global(self, t):
self.fill("global ")
interleave(lambda: self.write(", "), self.write, t.names)
+ def _Nonlocal(self, t):
+ self.fill("nonlocal ")
+ interleave(lambda: self.write(", "), self.write, t.names)
+
def _Yield(self, t):
self.write("(")
self.write("yield")
@@ -151,15 +142,15 @@
self.write(")")
def _Raise(self, t):
- self.fill('raise ')
- if t.type:
- self.dispatch(t.type)
- if t.inst:
- self.write(", ")
- self.dispatch(t.inst)
- if t.tback:
- self.write(", ")
- self.dispatch(t.tback)
+ self.fill("raise")
+ if not t.exc:
+ assert not t.cause
+ return
+ self.write(" ")
+ self.dispatch(t.exc)
+ if t.cause:
+ self.write(" from ")
+ self.dispatch(t.cause)
def _TryExcept(self, t):
self.fill("try")
@@ -192,21 +183,40 @@
self.write(" ")
self.dispatch(t.type)
if t.name:
- self.write(", ")
- self.dispatch(t.name)
+ self.write(" as ")
+ self.write(t.name)
self.enter()
self.dispatch(t.body)
self.leave()
def _ClassDef(self, t):
self.write("\n")
+ for deco in t.decorator_list:
+ self.fill("@")
+ self.dispatch(deco)
self.fill("class "+t.name)
- if t.bases:
- self.write("(")
- for a in t.bases:
- self.dispatch(a)
- self.write(", ")
- self.write(")")
+ self.write("(")
+ comma = False
+ for e in t.bases:
+ if comma: self.write(", ")
+ else: comma = True
+ self.dispatch(e)
+ for e in t.keywords:
+ if comma: self.write(", ")
+ else: comma = True
+ self.dispatch(e)
+ if t.starargs:
+ if comma: self.write(", ")
+ else: comma = True
+ self.write("*")
+ self.dispatch(t.starargs)
+ if t.kwargs:
+ if comma: self.write(", ")
+ else: comma = True
+ self.write("*")
+ self.dispatch(t.kwargs)
+ self.write(")")
+
self.enter()
self.dispatch(t.body)
self.leave()
@@ -219,6 +229,9 @@
self.fill("def "+t.name + "(")
self.dispatch(t.args)
self.write(")")
+ if t.returns:
+ self.write(" -> ")
+ self.dispatch(t.returns)
self.enter()
self.dispatch(t.body)
self.leave()
@@ -273,6 +286,9 @@
self.leave()
# expr
+ def _Bytes(self, t):
+ self.write(repr(t.s))
+
def _Str(self, tree):
self.write(repr(tree.s))
@@ -294,7 +310,7 @@
self.write(strnum)
self.write(")")
else:
- self.write(repr(t.n))
+ self.write(strnum)
def _List(self, t):
self.write("[")
@@ -315,6 +331,22 @@
self.dispatch(gen)
self.write(")")
+ def _SetComp(self, t):
+ self.write("{")
+ self.dispatch(t.elt)
+ for gen in t.generators:
+ self.dispatch(gen)
+ self.write("}")
+
+ def _DictComp(self, t):
+ self.write("{")
+ self.dispatch(t.key)
+ self.write(": ")
+ self.dispatch(t.value)
+ for gen in t.generators:
+ self.dispatch(gen)
+ self.write("}")
+
def _comprehension(self, t):
self.write(" for ")
self.dispatch(t.target)
@@ -333,14 +365,20 @@
self.dispatch(t.orelse)
self.write(")")
+ def _Set(self, t):
+ assert(t.elts) # should be at least one element
+ self.write("{")
+ interleave(lambda: self.write(", "), self.dispatch, t.elts)
+ self.write("}")
+
def _Dict(self, t):
self.write("{")
- def writem(xxx_todo_changeme):
- (k, v) = xxx_todo_changeme
+ def write_pair(pair):
+ (k, v) = pair
self.dispatch(k)
self.write(": ")
self.dispatch(v)
- interleave(lambda: self.write(", "), writem, zip(t.keys, t.values))
+ interleave(lambda: self.write(", "), write_pair, zip(t.keys, t.values))
self.write("}")
def _Tuple(self, t):
@@ -381,7 +419,7 @@
self.dispatch(e)
self.write(")")
- boolops = {_ast.And: 'and', _ast.Or: 'or'}
+ boolops = {ast.And: 'and', ast.Or: 'or'}
def _BoolOp(self, t):
self.write("(")
s = " %s " % self.boolops[t.op.__class__]
@@ -443,28 +481,55 @@
def _ExtSlice(self, t):
interleave(lambda: self.write(', '), self.dispatch, t.dims)
+ # argument
+ def _arg(self, t):
+ self.write(t.arg)
+ if t.annotation:
+ self.write(": ")
+ self.dispatch(t.annotation)
+
# others
def _arguments(self, t):
first = True
- nonDef = len(t.args)-len(t.defaults)
- for a in t.args[0:nonDef]:
+ # normal arguments
+ defaults = [None] * (len(t.args) - len(t.defaults)) + t.defaults
+ for a, d in zip(t.args, defaults):
if first:first = False
else: self.write(", ")
self.dispatch(a)
- for a,d in zip(t.args[nonDef:], t.defaults):
+ if d:
+ self.write("=")
+ self.dispatch(d)
+
+ # varargs, or bare '*' if no varargs but keyword-only arguments present
+ if t.vararg or t.kwonlyargs:
if first:first = False
else: self.write(", ")
- self.dispatch(a),
- self.write("=")
- self.dispatch(d)
- if t.vararg:
- if first:first = False
- else: self.write(", ")
- self.write("*"+t.vararg)
+ self.write("*")
+ if t.vararg:
+ self.write(t.vararg)
+ if t.varargannotation:
+ self.write(": ")
+ self.dispatch(t.varargannotation)
+
+ # keyword-only arguments
+ if t.kwonlyargs:
+ for a, d in zip(t.kwonlyargs, t.kw_defaults):
+ if first:first = False
+ else: self.write(", ")
+ self.dispatch(a),
+ if d:
+ self.write("=")
+ self.dispatch(d)
+
+ # kwargs
if t.kwarg:
if first:first = False
else: self.write(", ")
self.write("**"+t.kwarg)
+ if t.kwargannotation:
+ self.write(": ")
+ self.dispatch(t.kwargannotation)
def _keyword(self, t):
self.write(t.arg)