1
r"""Utilities to compile possibly incomplete Python source code.
3
This module provides two interfaces, broadly similar to the builtin
4
function compile(), which take program text, a filename and a 'mode'
7
- Return code object if the command is complete and valid
8
- Return None if the command is incomplete
9
- Raise SyntaxError, ValueError or OverflowError if the command is a
10
syntax error (OverflowError and ValueError can be produced by
15
First, check if the source consists entirely of blank lines and
16
comments; if so, replace it with 'pass', because the built-in
17
parser doesn't always do the right thing for these.
19
Compile three times: as is, with \n, and with \n\n appended. If it
20
compiles as is, it's complete. If it compiles with one \n appended,
21
we expect more. If it doesn't compile either way, we compare the
22
error we get when compiling with \n or \n\n appended. If the errors
23
are the same, the code is broken. But if the errors are different, we
24
expect more. Not intuitive; not even guaranteed to hold in future
25
releases; but this matches the compiler's behavior from Python 1.4
26
through 2.2, at least.
30
It is possible (but not likely) that the parser stops parsing with a
31
successful outcome before reaching the end of the source; in this
32
case, trailing symbols may be ignored instead of causing an error.
33
For example, a backslash followed by two newlines may be followed by
34
arbitrary garbage. This will be fixed once the API for the parser is
37
The two interfaces are:
39
compile_command(source, filename, symbol):
41
Compiles a single command in the manner described above.
45
Instances of this class have __call__ methods identical in
46
signature to compile_command; the difference is that if the
47
instance compiles program text containing a __future__ statement,
48
the instance 'remembers' and compiles all subsequent program texts
49
with the statement in force.
51
The module also provides another class:
55
Instances of this class act like the built-in function compile,
56
but with 'memory' in the sense described above.
61
_features = [getattr(__future__, fname)
62
for fname in __future__.all_feature_names]
64
__all__ = ["compile_command", "Compile", "CommandCompiler"]
66
PyCF_DONT_IMPLY_DEDENT = 0x200 # Matches pythonrun.h
68
def _maybe_compile(compiler, source, filename, symbol):
69
# Check for source consisting of only blank lines and comments
70
for line in source.split("\n"):
72
if line and line[0] != '#':
73
break # Leave it alone
76
source = "pass" # Replace it with a 'pass' statement
78
err = err1 = err2 = None
79
code = code1 = code2 = None
82
code = compiler(source, filename, symbol)
83
except SyntaxError, err:
87
code1 = compiler(source + "\n", filename, symbol)
88
except SyntaxError, err1:
92
code2 = compiler(source + "\n\n", filename, symbol)
93
except SyntaxError, err2:
98
if not code1 and repr(err1) == repr(err2):
99
raise SyntaxError, err1
101
def _compile(source, filename, symbol):
102
return compile(source, filename, symbol, PyCF_DONT_IMPLY_DEDENT)
104
def compile_command(source, filename="<input>", symbol="single"):
105
r"""Compile a command and determine whether it is incomplete.
109
source -- the source string; may contain \n characters
110
filename -- optional filename from which source was read; default
112
symbol -- optional grammar start symbol; "single" (default) or "eval"
114
Return value / exceptions raised:
116
- Return a code object if the command is complete and valid
117
- Return None if the command is incomplete
118
- Raise SyntaxError, ValueError or OverflowError if the command is a
119
syntax error (OverflowError and ValueError can be produced by
122
return _maybe_compile(_compile, source, filename, symbol)
125
"""Instances of this class behave much like the built-in compile
126
function, but if one is used to compile text containing a future
127
statement, it "remembers" and compiles all subsequent program texts
128
with the statement in force."""
130
self.flags = PyCF_DONT_IMPLY_DEDENT
132
def __call__(self, source, filename, symbol):
133
codeob = compile(source, filename, symbol, self.flags, 1)
134
for feature in _features:
135
if codeob.co_flags & feature.compiler_flag:
136
self.flags |= feature.compiler_flag
139
class CommandCompiler:
140
"""Instances of this class have __call__ methods identical in
141
signature to compile_command; the difference is that if the
142
instance compiles program text containing a __future__ statement,
143
the instance 'remembers' and compiles all subsequent program texts
144
with the statement in force."""
147
self.compiler = Compile()
149
def __call__(self, source, filename="<input>", symbol="single"):
150
r"""Compile a command and determine whether it is incomplete.
154
source -- the source string; may contain \n characters
155
filename -- optional filename from which source was read;
157
symbol -- optional grammar start symbol; "single" (default) or
160
Return value / exceptions raised:
162
- Return a code object if the command is complete and valid
163
- Return None if the command is incomplete
164
- Raise SyntaxError, ValueError or OverflowError if the command is a
165
syntax error (OverflowError and ValueError can be produced by
168
return _maybe_compile(self.compiler, source, filename, symbol)
1
r"""Utilities to compile possibly incomplete Python source code.
3
This module provides two interfaces, broadly similar to the builtin
4
function compile(), which take program text, a filename and a 'mode'
7
- Return code object if the command is complete and valid
8
- Return None if the command is incomplete
9
- Raise SyntaxError, ValueError or OverflowError if the command is a
10
syntax error (OverflowError and ValueError can be produced by
15
First, check if the source consists entirely of blank lines and
16
comments; if so, replace it with 'pass', because the built-in
17
parser doesn't always do the right thing for these.
19
Compile three times: as is, with \n, and with \n\n appended. If it
20
compiles as is, it's complete. If it compiles with one \n appended,
21
we expect more. If it doesn't compile either way, we compare the
22
error we get when compiling with \n or \n\n appended. If the errors
23
are the same, the code is broken. But if the errors are different, we
24
expect more. Not intuitive; not even guaranteed to hold in future
25
releases; but this matches the compiler's behavior from Python 1.4
26
through 2.2, at least.
30
It is possible (but not likely) that the parser stops parsing with a
31
successful outcome before reaching the end of the source; in this
32
case, trailing symbols may be ignored instead of causing an error.
33
For example, a backslash followed by two newlines may be followed by
34
arbitrary garbage. This will be fixed once the API for the parser is
37
The two interfaces are:
39
compile_command(source, filename, symbol):
41
Compiles a single command in the manner described above.
45
Instances of this class have __call__ methods identical in
46
signature to compile_command; the difference is that if the
47
instance compiles program text containing a __future__ statement,
48
the instance 'remembers' and compiles all subsequent program texts
49
with the statement in force.
51
The module also provides another class:
55
Instances of this class act like the built-in function compile,
56
but with 'memory' in the sense described above.
61
_features = [getattr(__future__, fname)
62
for fname in __future__.all_feature_names]
64
__all__ = ["compile_command", "Compile", "CommandCompiler"]
66
PyCF_DONT_IMPLY_DEDENT = 0x200 # Matches pythonrun.h
68
def _maybe_compile(compiler, source, filename, symbol):
69
# Check for source consisting of only blank lines and comments
70
for line in source.split("\n"):
72
if line and line[0] != '#':
73
break # Leave it alone
76
source = "pass" # Replace it with a 'pass' statement
78
err = err1 = err2 = None
79
code = code1 = code2 = None
82
code = compiler(source, filename, symbol)
83
except SyntaxError, err:
87
code1 = compiler(source + "\n", filename, symbol)
88
except SyntaxError, err1:
92
code2 = compiler(source + "\n\n", filename, symbol)
93
except SyntaxError, err2:
98
if not code1 and repr(err1) == repr(err2):
99
raise SyntaxError, err1
101
def _compile(source, filename, symbol):
102
return compile(source, filename, symbol, PyCF_DONT_IMPLY_DEDENT)
104
def compile_command(source, filename="<input>", symbol="single"):
105
r"""Compile a command and determine whether it is incomplete.
109
source -- the source string; may contain \n characters
110
filename -- optional filename from which source was read; default
112
symbol -- optional grammar start symbol; "single" (default) or "eval"
114
Return value / exceptions raised:
116
- Return a code object if the command is complete and valid
117
- Return None if the command is incomplete
118
- Raise SyntaxError, ValueError or OverflowError if the command is a
119
syntax error (OverflowError and ValueError can be produced by
122
return _maybe_compile(_compile, source, filename, symbol)
125
"""Instances of this class behave much like the built-in compile
126
function, but if one is used to compile text containing a future
127
statement, it "remembers" and compiles all subsequent program texts
128
with the statement in force."""
130
self.flags = PyCF_DONT_IMPLY_DEDENT
132
def __call__(self, source, filename, symbol):
133
codeob = compile(source, filename, symbol, self.flags, 1)
134
for feature in _features:
135
if codeob.co_flags & feature.compiler_flag:
136
self.flags |= feature.compiler_flag
139
class CommandCompiler:
140
"""Instances of this class have __call__ methods identical in
141
signature to compile_command; the difference is that if the
142
instance compiles program text containing a __future__ statement,
143
the instance 'remembers' and compiles all subsequent program texts
144
with the statement in force."""
147
self.compiler = Compile()
149
def __call__(self, source, filename="<input>", symbol="single"):
150
r"""Compile a command and determine whether it is incomplete.
154
source -- the source string; may contain \n characters
155
filename -- optional filename from which source was read;
157
symbol -- optional grammar start symbol; "single" (default) or
160
Return value / exceptions raised:
162
- Return a code object if the command is complete and valid
163
- Return None if the command is incomplete
164
- Raise SyntaxError, ValueError or OverflowError if the command is a
165
syntax error (OverflowError and ValueError can be produced by
168
return _maybe_compile(self.compiler, source, filename, symbol)
added
removed
python/Lib/codeop.py
