mirror of https://github.com/python/cpython
Moved compile_command() to a file of its own (codeop.py).
This commit is contained in:
parent
c41c1a984e
commit
5d42b5b74d
85
Lib/code.py
85
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:
|
||||
|
|
Loading…
Reference in New Issue