def abstract_code_from_function(func):
'''
Converts the body of the function to abstract code
Parameters
----------
func : function, str or ast.FunctionDef
The function object to convert. Note that the arguments to the
function are ignored.
Returns
-------
func : AbstractCodeFunction
The corresponding abstract code function
Raises
------
SyntaxError
If unsupported features are used such as if statements or indexing.
'''
if callable(func):
code = deindent(inspect.getsource(func))
funcnode = ast.parse(code, mode='exec').body[0]
elif isinstance(func, str):
funcnode = ast.parse(func, mode='exec').body[0]
elif func.__class__ is ast.FunctionDef:
funcnode = func
else:
raise TypeError("Unsupported function type")
if funcnode.args.vararg is not None:
raise SyntaxError("No support for variable number of arguments")
if funcnode.args.kwarg is not None:
raise SyntaxError("No support for arbitrary keyword arguments")
if len(funcnode.args.defaults):
raise SyntaxError("No support for default values in functions")
nodes = funcnode.body
nr = NodeRenderer()
lines = []
return_expr = None
for node in nodes:
if node.__class__ is ast.Return:
return_expr = nr.render_node(node.value)
break
else:
lines.append(nr.render_node(node))
abstract_code = '\n'.join(lines)
try:
# Python 2
args = [arg.id for arg in funcnode.args.args]
except AttributeError:
# Python 3
args = [arg.arg for arg in funcnode.args.args]
name = funcnode.name
return AbstractCodeFunction(name, args, abstract_code, return_expr)
def substitute_abstract_code_functions(code, funcs):
'''
Performs inline substitution of all the functions in the code
Parameters
----------
code : str
The abstract code to make inline substitutions into.
funcs : list, dict or set of AbstractCodeFunction
The function substitutions to use, note in the case of a dict, the
keys are ignored and the function name is used.
Returns
-------
code : str
The code with inline substitutions performed.
'''
if isinstance(funcs, (list, set)):
newfuncs = dict()
for f in funcs:
newfuncs[f.name] = f
funcs = newfuncs
code = deindent(code)
lines = ast.parse(code, mode='exec').body
# This is a slightly nasty hack, but basically we just check by looking at
# the existing identifiers how many inline operations have already been
# performed by previous calls to this function
ids = get_identifiers(code)
funcstarts = {}
for func in funcs.values():
subids = set([id for id in ids if id.startswith('_inline_'+func.name+'_')])
subids = set([id.replace('_inline_'+func.name+'_', '') for id in subids])
alli = []
for subid in subids:
p = subid.find('_')
if p>0:
subid = subid[:p]
i = int(subid)
alli.append(i)
if len(alli)==0:
i = 0
else:
i = max(alli)+1
funcstarts[func.name] = i
# Now we rewrite all the lines, replacing each line with a sequence of
# lines performing the inlining
newlines = []
for line in lines:
for func in funcs.values():
rw = FunctionRewriter(func, funcstarts[func.name])
line = rw.visit(line)
newlines.extend(rw.pre)
funcstarts[func.name] = rw.numcalls
newlines.append(line)
# Now we render to a code string
nr = NodeRenderer()
newcode = '\n'.join(nr.render_node(line) for line in newlines)
# We recurse until no changes in the code to ensure that all functions
# are expanded if one function refers to another, etc.
if newcode==code:
return newcode
else:
return substitute_abstract_code_functions(newcode, funcs)
