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v0.8.1
v0.8.1
https://github.com/python/cpython
Tip revision: 9b24649118b99987a42fcab0a9793bd5d2b0d762 authored by cvs2svn on 15 August 1997, 20:18:44 UTC
This commit was manufactured by cvs2svn to create tag 'r15a3'.
This commit was manufactured by cvs2svn to create tag 'r15a3'.
Tip revision: 9b24649
code.py
"""Utilities dealing with code objects."""
def compile_command(source, filename="<input>", symbol="single"):
r"""Compile a command and determine whether it is incomplete.
Arguments:
source -- the source string; may contain \n characters
filename -- optional filename from which source was read; default "<input>"
symbol -- optional grammar start symbol; "single" (default) or "eval"
Return value / exception raised:
- Return a code object if the command is complete and valid
- Return None if the command is incomplete
- Raise SyntaxError if the command is a syntax error
Approach:
Compile three times: as is, with \n, and with \n\n appended. If
it compiles as is, it's complete. If it compiles with one \n
appended, we expect more. If it doesn't compile either way, we
compare the error we get when compiling with \n or \n\n appended.
If the errors are the same, the code is broken. But if the errors
are different, we expect more. Not intuitive; not even guaranteed
to hold in future releases; but this matches the compiler's
behavior in Python 1.4 and 1.5.
"""
err = err1 = err2 = None
code = code1 = code2 = None
try:
code = compile(source, filename, symbol)
except SyntaxError, err:
pass
try:
code1 = compile(source + "\n", filename, symbol)
except SyntaxError, err1:
pass
try:
code2 = compile(source + "\n\n", filename, symbol)
except SyntaxError, err2:
pass
if code:
return code
if not code1 and err1 == err2:
raise SyntaxError, err1