diff options
Diffstat (limited to 'Lib/code.py')
-rw-r--r-- | Lib/code.py | 85 |
1 files changed, 3 insertions, 82 deletions
diff --git a/Lib/code.py b/Lib/code.py index 94e7777..6d8c35c 100644 --- a/Lib/code.py +++ b/Lib/code.py @@ -1,92 +1,13 @@ -"""Utilities dealing with code objects. +"""Utilities needed to emulate Python's interactive interpreter. Inspired by similar code by Jeff Epler and Fredrik Lundh. """ + import sys import string import traceback - -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 / exceptions raised: - - - Return a code object if the command is complete and valid - - Return None if the command is incomplete - - Raise SyntaxError or OverflowError if the command is a syntax error - (OverflowError if the error is in a numeric constant) - - Approach: - - First, check if the source consists entirely of blank lines and - comments; if so, replace it with 'pass', because the built-in - parser doesn't always do the right thing for these. - - 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 from Python 1.4 through 1.5.2, at least. - - Caveat: - - It is possible (but not likely) that the parser stops parsing - with a successful outcome before reaching the end of the source; - in this case, trailing symbols may be ignored instead of causing an - error. For example, a backslash followed by two newlines may be - followed by arbitrary garbage. This will be fixed once the API - for the parser is better. - - """ - - # Check for source consisting of only blank lines and comments - for line in string.split(source, "\n"): - line = string.strip(line) - if line and line[0] != '#': - break # Leave it alone - else: - source = "pass" # Replace it with a 'pass' statement - - 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 - try: - e1 = err1.__dict__ - except AttributeError: - e1 = err1 - try: - e2 = err2.__dict__ - except AttributeError: - e2 = err2 - if not code1 and e1 == e2: - raise SyntaxError, err1 +from codeop import compile_command class InteractiveInterpreter: |