def __init__(self, *res, **options):
""" Compiles a regular expression. Once compiled, it can be used
repeatedly to search, split or replace text in a string.
:param res: List of Bytestring expressions to compile
:param kwargs: Config options to pass (flags bitmask,
size_limit,
dfa_size_limit)
"""
flags = options.pop('flags', DEFAULT_FLAGS)
if not all(isinstance(re, bytes) for re in res):
raise TypeError("'rure.lib.RureSet' must be instantiated with a "
"list of bytestrings as first argument.")
self._err = ffi.gc(_lib.rure_error_new(), _lib.rure_error_free)
self._opts = ffi.gc(_lib.rure_options_new(), _lib.rure_options_free)
self.options = options
if 'size_limit' in options:
_lib.rure_options_size_limit(self._opts, options['size_limit'])
if 'dfa_size_limit' in options:
_lib.rure_options_dfa_size_limit(self._opts,
options['dfa_size_limit'])
patterns = []
patterns_lengths = []
for re in res:
patterns.append(ffi.new("uint8_t []", re))
patterns_lengths.append(len(re))
s = checked_call(_lib.rure_compile_set, self._err,
ffi.new("uint8_t *[]", patterns),
ffi.new("size_t []", patterns_lengths), len(patterns),
flags, self._opts)
self._ptr = ffi.gc(s, _lib.rure_set_free)
def captures(self, haystack, start=0):
"""Returns the capture groups corresponding to the leftmost-first match
in text. Capture group 0 always corresponds to the entire match.
If no match is found, then None is returned.
You should only use captures if you need access to submatches.
Otherwise, find is faster for discovering the location of the overall
match.
"""
hlen = len(haystack)
captures = ffi.gc(_lib.rure_captures_new(self._ptr),
_lib.rure_captures_free)
match = ffi.new('rure_match *')
if _lib.rure_find_captures(
self._ptr,
haystack,
hlen,
start,
captures
):
return self.capture_cls(*[
RureMatch(match.start, match.end)
if _lib.rure_captures_at(captures, i, match) else None
for i in range(0, _lib.rure_captures_len(captures))
])
def matches(self, haystack, start=0):
"""
Returns a list of booleans indicating whether the regex at each index
was matched in the string given
"""
matches = ffi.new("bool[]", len(self))
_lib.rure_set_matches(self._ptr, haystack, len(haystack), start,
matches)
return [bool(match) for match in matches]
def shortest_match(self, haystack, start=0):
"""Returns end location if and only if re matches anywhere in
text. The end location is the place at which the regex engine
determined that a match exists, but may occur before the end of
the proper leftmost-first match.
"""
hlen = len(haystack)
end = ffi.new('size_t *')
if _lib.rure_shortest_match(self._ptr, haystack, hlen, start, end):
return end[0]
def find(self, haystack, start=0):
""" Returns the start and end byte range of the leftmost-first match
in text. If no match exists, then None is returned.
Note that this should only be used if you want to discover the position
of the match. Testing the existence of a match is faster if you use
is_match.
"""
match = ffi.new('rure_match *')
if _lib.rure_find(self._ptr, haystack, len(haystack), start, match):
return RureMatch(match.start, match.end)
def capture_names(self):
""" An iterator over the names of all possible captures.
None indicates an unnamed capture; the first element (capture 0,
the whole matched region) is always unnamed.
"""
cn_iter = ffi.gc(_lib.rure_iter_capture_names_new(self._ptr),
_lib.rure_iter_capture_names_free)
ptr = ffi.new('char **')
while _lib.rure_iter_capture_names_next(cn_iter, ptr):
name = ffi.string(ptr[0])
if name:
yield name
else:
yield None
def find_iter(self, haystack, start=0):
"""Returns the capture groups corresponding to the leftmost-first match
in text. Capture group 0 always corresponds to the entire match.
If no match is found, then None is returned.
You should only use captures if you need access to submatches.
Otherwise, find is faster for discovering the location of the overall
match.
"""
hlen = len(haystack)
find_iter = ffi.gc(_lib.rure_iter_new(self._ptr), _lib.rure_iter_free)
match = ffi.new('rure_match *')
while _lib.rure_iter_next(find_iter, haystack, hlen, match):
yield RureMatch(match.start, match.end)
def captures_iter(self, haystack, start=0):
"""Returns an iterator over all the non-overlapping capture groups
matched in text. This is operationally the same as find_iter,
except it yields information about submatches.
"""
hlen = len(haystack)
captures = ffi.gc(_lib.rure_captures_new(self._ptr),
_lib.rure_captures_free)
captures_iter = ffi.gc(_lib.rure_iter_new(self._ptr),
_lib.rure_iter_free)
match = ffi.new('rure_match *')
while _lib.rure_iter_next_captures(captures_iter, haystack, hlen,
captures):
yield self.capture_cls(*[
RureMatch(match.start, match.end) if _lib.
rure_captures_at(captures, i, match) else None
for i in range(0, _lib.rure_captures_len(captures))
])