def __add_case_fold(sm, Flags, trigger_set, start_state_idx, target_state_idx):
for interval in trigger_set.get_intervals(PromiseToTreatWellF=True):
for i in range(interval.begin, interval.end):
fold = ucs_case_fold.get_fold_set(i, Flags)
for x in fold:
if type(x) == list:
__add_intermediate_states(sm, x, start_state_idx, target_state_idx)
else:
trigger_set.add_interval(Interval(x, x+1))
def snap_case_folded_pattern(sh, PatternDict, NumberSetF=False):
"""Parse a case fold expression of the form \C(..){ R } or \C{ R }.
Assume that '\C' has been snapped already from the stream.
See function ucs_case_fold_parser.get_fold_set() for details
about case folding.
"""
def __add_intermediate_states(sm, character_list, start_state_idx, target_state_idx):
next_idx = start_state_idx
for letter in character_list[:-1]:
next_idx = sm.add_transition(next_idx, letter)
sm.add_transition(next_idx, character_list[-1], target_state_idx)
def __add_case_fold(sm, Flags, trigger_set, start_state_idx, target_state_idx):
for interval in trigger_set.get_intervals(PromiseToTreatWellF=True):
for i in range(interval.begin, interval.end):
fold = ucs_case_fold.get_fold_set(i, Flags)
for x in fold:
if type(x) == list:
__add_intermediate_states(sm, x, start_state_idx, target_state_idx)
else:
trigger_set.add_interval(Interval(x, x+1))
pos = sh.tell()
skip_whitespace(sh)
# -- parse the optional options in '(' ')' brackets
if not check(sh, "("):
# By default 'single' and 'multi' character case folds are active
if NumberSetF: flag_txt = "s"
else: flag_txt = "sm"
else:
flag_txt = read_until_character(sh, ")")
if flag_txt == "":
sh.seek(pos)
error_msg("Missing closing ')' in case fold expression.", sh)
flag_txt = flag_txt.replace(" ", "").replace("\t", "").replace("\n", "")
for letter in flag_txt:
if letter not in "smt":
sh.seek(pos)
error_msg("Letter '%s' not permitted as case fold option.\n" % letter + \
"Options are: 's' for simple case fold.\n" + \
" 'm' for multi character sequence case fold.\n" + \
" 't' for special turkish case fold rules.", sh)
if NumberSetF and letter == "m":
sh.seek(pos)
error_msg("Option 'm' not permitted as case fold option in set expression.\n" + \
"Set expressions cannot absorb multi character sequences.", sh)
skip_whitespace(sh)
result = snap_curly_bracketed_expression(sh, PatternDict, "case fold operator", "C")[0]
if NumberSetF:
trigger_set = result.get_number_set()
if trigger_set is None:
error_msg("Expression in case fold does not result in character set.\n" +
"The content in '\\C{content}' may start with '[' or '[:'.", sh)
# -- perform the case fold for Sets!
for interval in trigger_set.get_intervals(PromiseToTreatWellF=True):
for i in range(interval.begin, interval.end):
fold = ucs_case_fold.get_fold_set(i, flag_txt)
for x in fold:
assert type(x) != list
trigger_set.add_interval(Interval(x, x+1))
result = trigger_set
else:
# -- perform the case fold for State Machines!
for state_idx, state in result.states.items():
for target_state_idx, trigger_set in state.target_map.get_map().items():
__add_case_fold(result, flag_txt, trigger_set, state_idx, target_state_idx)
return result
def do(sh, PatternDict, snap_expression=None, snap_set_expression=None):
"""Parse a case fold expression of the form \C(..){ R } or \C{ R }.
Assume that '\C' has been snapped already from the stream.
See function ucs_case_fold_parser.get_fold_set() for details
about case folding.
snap_expression is not None, then snap_expression is the function
to parse a RE and the caller
expects a state machine.
snap_set_expression is not None, then snap_set_expression is the
function to parse a character
set and caller expects a
NumberSet object.
"""
pos = sh.tell()
skip_whitespace(sh)
# -- parse the optional options in '(' ')' brackets
if not check(sh, "("):
# By default 'single' and 'multi' character case folds are active
if snap_set_expression is not None: flag_txt = "s"
else: flag_txt = "sm"
else:
flag_txt = read_until_character(sh, ")")
if flag_txt == "":
sh.seek(pos)
error_msg("Missing closing ')' in case fold expression.", sh)
flag_txt = flag_txt.replace(" ", "").replace("\t",
"").replace("\n", "")
for letter in flag_txt:
if letter not in "smt":
sh.seek(pos)
error_msg("Letter '%s' not permitted as case fold option.\n" % letter + \
"Options are: 's' for simple case fold.\n" + \
" 'm' for multi character sequence case fold.\n" + \
" 't' for special turkish case fold rules.", sh)
if snap_set_expression is not None and letter == "m":
sh.seek(pos)
error_msg("Option 'm' not permitted as case fold option in set expression.\n" + \
"Set expressions cannot absorb multi character sequences.", sh)
skip_whitespace(sh)
# -- parse the expression in '{' '}' which is subject to case folding
if not check(sh, "{"):
sh.seek(pos)
error_msg("Missing '{' for case fold expression.", sh)
skip_whitespace(sh)
if snap_set_expression is not None:
trigger_set = snap_set_expression(sh, PatternDict)
if trigger_set is None:
error_msg(
"Missing character set for case fold in set expression.\n" +
"The content in '\\C{content}' should start with '[' or '[:'.",
sh)
# -- perform the case fold for Sets!
for interval in trigger_set.get_intervals(PromiseToTreatWellF=True):
for i in range(interval.begin, interval.end):
fold = ucs_case_fold.get_fold_set(i, flag_txt)
for x in fold:
assert type(x) != list
trigger_set.add_interval(Interval(x, x + 1))
result = trigger_set
else:
sm = snap_expression(sh, PatternDict)
if sm is None:
error_msg(
"Missing expression for case fold '\C'.\n" +
"The content in '\\C{content}' should start with '[' or '[:'.",
sh)
# -- perform the case fold for State Machines!
for state_idx, state in sm.states.items():
transitions = state.transitions()
for target_state_idx, trigger_set in transitions.get_map().items():
__add_case_fold(sm, flag_txt, trigger_set, state_idx,
target_state_idx)
result = sm
if not check(sh, "}"):
sh.seek(pos)
error_msg("Missing '}' for case fold expression.", sh)
return result