Re: [IronPython] IPython is breathing but there's a compile() problem
This is probably a dup of 12907
http://ironpython.codeplex.com/WorkItem/View.aspx?WorkItemId=12907
That being said the more test cases for this the better - this option isn't
really documented. Also if anyone can provide insight into exactly how this is
supposed to behave that'd be great. But my guess is that we'll have a tail of
bugs around this until we can nail down the behavior and get it right. Anyway,
I'll take a look at fixing the existing issues here. Wanting to implement a
REPL from Python seems like it's the thing everyone likes to try :)
From: users-boun...@lists.ironpython.com
[mailto:users-boun...@lists.ironpython.com] On Behalf Of Mike Krell
Sent: Monday, May 25, 2009 10:00 AM
To: Discussion of IronPython
Subject: [IronPython] IPython is breathing but there's a compile() problem
Now that 2.6B1 has frames support, I've started playing with IronPython under
IPython again. I've managed to get a command prompt up (some modules are
missing, but the only crucial one is codeop, which I stole from the standard
distribution).
However, there's a problem with entering multiline code snippets interactively.
With CPython, this looks like:
In [21]: if 1:
: if 1:
:
(The indentation looks wrong without a fixed-width font, but you get the idea.)
With IronPython, the second if 1: line blows up with a syntax error. This
boils down to a difference in the way the compile() builtin works as used by
the codeop module.
I've written this up as a bug at codeplex. Please vote for the bug here:
http://ironpython.codeplex.com/WorkItem/View.aspx?WorkItemId=22692
It would be awesome if we could have a good IronPython + IPython story before
2.6 is released!
Below are more details about the problem as described in the bug description.
Mike
bug description at codeplex follows
compile() behaves differently than in CPython in the presence of incomplete
multiline code snippets. Fixing this incompatiblity is necessary for running
IronPython under IPython.
Here is a sample program illustrating the problem. The program is a
modification of the code used in the standard codeop module by IPython to
determine when to provide a continuation prompt for a multiline snippet.
def testcompile(source, flags):
err = err1 = err2 = None
code = code1 = code2 = None
try:
code = compile(source, dummy, single, flags, 1)
except SyntaxError, err:
pass
try:
code1 = compile(source + \n, dummy, single, flags, 1)
except SyntaxError, err1:
pass
try:
code2 = compile(source + \n\n, dummy, single, flags, 1)
except SyntaxError, err2:
pass
print for source = '%s' and flags = %d % (source, flags),
if code:
print Syntax valid
elif not code1 and repr(err1) == repr(err2):
print Syntax error!
print
print err1:, repr(err1)
print err2:, repr(err2)
else:
print Continue on next line
print
print err1:, repr(err1)
print err2:, repr(err2)
print
# 0x200 is PyCF_DONT_IMPLY_DEDENT
testcompile(if 1:, 0x200)
testcompile(if 1:, 0)
testcompile(if 1:\n if 1:, 0x200)
testcompile(if 1:\n if 1:, 0)
Under CPython (2.6.1) the output is:
for source = 'if 1:' and flags = 512 Continue on next line
err1: SyntaxError('unexpected EOF while parsing', ('dummy', 1, 6, 'if 1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 2, 1, '\n'))
for source = 'if 1:' and flags = 0 Continue on next line
err1: SyntaxError('unexpected EOF while parsing', ('dummy', 1, 6, 'if 1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 2, 1, '\n'))
for source = 'if 1:
if 1:' and flags = 512 Continue on next line
err1: IndentationError('expected an indented block', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 3, 1, '\n'))
for source = 'if 1:
if 1:' and flags = 0 Continue on next line
err1: IndentationError('expected an indented block', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 3, 1, '\n'))
In all cases the code correctly outputs Continue on next line since both
snippets are incomplete but otherwise valid python.
For IronPython 2.6 Beta 1 the output is:
for source = 'if 1:' and flags = 512 Continue on next line
err1: IndentationError(unexpected token 'eof', ('dummy', 2, 1, ''))
err2: IndentationError(unexpected token 'eof', ('dummy', 3, 1,
Re: [IronPython] IPython is breathing but there's a compile() problem
On Tue, May 26, 2009 at 10:50 AM, Michael Foord fuzzy...@voidspace.org.ukwrote I wonder if it isn't in fact caused by the fact that the repr of an IronPython syntax error doesn't change if the you add new lines to the source code you are compiling. Yes, in this case that is the crux of the issue. Mike ___ Users mailing list Users@lists.ironpython.com http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
[IronPython] IPython is breathing but there's a compile() problem
Now that 2.6B1 has frames support, I've started playing with IronPython
under IPython again. I've managed to get a command prompt up (some modules
are missing, but the only crucial one is codeop, which I stole from the
standard distribution).
However, there's a problem with entering multiline code snippets
interactively. With CPython, this looks like:
In [21]: if 1:
: if 1:
:
(The indentation looks wrong without a fixed-width font, but you get the
idea.)
With IronPython, the second if 1: line blows up with a syntax error. This
boils down to a difference in the way the compile() builtin works as used by
the codeop module.
I've written this up as a bug at codeplex. Please vote for the bug here:
http://ironpython.codeplex.com/WorkItem/View.aspx?WorkItemId=22692
It would be awesome if we could have a good IronPython + IPython story
before 2.6 is released!
Below are more details about the problem as described in the bug
description.
Mike
bug description at codeplex follows
compile() behaves differently than in CPython in the presence of incomplete
multiline code snippets. Fixing this incompatiblity is necessary for
running IronPython under IPython.
Here is a sample program illustrating the problem. The program is a
modification of the code used in the standard codeop module by IPython to
determine when to provide a continuation prompt for a multiline snippet.
def testcompile(source, flags):
err = err1 = err2 = None
code = code1 = code2 = None
try:
code = compile(source, dummy, single, flags, 1)
except SyntaxError, err:
pass
try:
code1 = compile(source + \n, dummy, single, flags, 1)
except SyntaxError, err1:
pass
try:
code2 = compile(source + \n\n, dummy, single, flags, 1)
except SyntaxError, err2:
pass
print for source = '%s' and flags = %d % (source, flags),
if code:
print Syntax valid
elif not code1 and repr(err1) == repr(err2):
print Syntax error!
print
print err1:, repr(err1)
print err2:, repr(err2)
else:
print Continue on next line
print
print err1:, repr(err1)
print err2:, repr(err2)
print
# 0x200 is PyCF_DONT_IMPLY_DEDENT
testcompile(if 1:, 0x200)
testcompile(if 1:, 0)
testcompile(if 1:\n if 1:, 0x200)
testcompile(if 1:\n if 1:, 0)
Under CPython (2.6.1) the output is:
for source = 'if 1:' and flags = 512 Continue on next line
err1: SyntaxError('unexpected EOF while parsing', ('dummy', 1, 6, 'if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 2, 1, '\n'))
for source = 'if 1:' and flags = 0 Continue on next line
err1: SyntaxError('unexpected EOF while parsing', ('dummy', 1, 6, 'if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 2, 1, '\n'))
for source = 'if 1:
if 1:' and flags = 512 Continue on next line
err1: IndentationError('expected an indented block', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 3, 1, '\n'))
for source = 'if 1:
if 1:' and flags = 0 Continue on next line
err1: IndentationError('expected an indented block', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError('expected an indented block', ('dummy', 3, 1, '\n'))
In all cases the code correctly outputs Continue on next line since both
snippets are incomplete but otherwise valid python.
For IronPython 2.6 Beta 1 the output is:
for source = 'if 1:' and flags = 512 Continue on next line
err1: IndentationError(unexpected token 'eof', ('dummy', 2, 1, ''))
err2: IndentationError(unexpected token 'eof', ('dummy', 3, 1, ''))
for source = 'if 1:' and flags = 0 Continue on next line
err1: IndentationError(unexpected token 'eof', ('dummy', 2, 1, ''))
err2: IndentationError(unexpected token 'eof', ('dummy', 3, 1, ''))
for source = 'if 1:
if 1:' and flags = 512 Syntax error!
err1: IndentationError(unexpected token 'eof', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError(unexpected token 'eof', ('dummy', 2, 8, ' if
1:\n'))
for source = 'if 1:
if 1:' and flags = 0 Syntax error!
err1: IndentationError(unexpected token 'eof', ('dummy', 2, 8, ' if
1:\n'))
err2: IndentationError(unexpected token 'eof', ('dummy', 2, 8, ' if
1:\n'))
The second snippet is misinterpreted as being a syntax error instead of
merely incomplete.
This is very similar to the
