def snap_term(stream, PatternDict):
"""term: primary
primary term
"""
__debug_entry("term", stream)
# -- primary
result = snap_primary(stream, PatternDict)
__debug_print("##primary(in term):", result)
if result == None: return __debug_exit(None, stream)
position_1 = stream.tell()
# -- optional 'term'
result_2 = snap_term(stream, PatternDict)
__debug_print("##term(in term):", result_2)
if result_2 == None:
stream.seek(position_1)
return __debug_exit(result, stream)
## print "##1:", result.get_string(NormalizeF=False)
## print "##2:", result_2.get_string(NormalizeF=False)
result = sequentialize.do([result, result_2],
MountToFirstStateMachineF=True,
CloneRemainingStateMachinesF=False)
return __debug_exit(construct.beautify(result), stream)
def snap_expression(stream, PatternDict):
"""expression: term
term | expression
"""
__debug_entry("expression", stream)
# -- term
result = snap_term(stream, PatternDict)
if result == None:
return __debug_exit(None, stream)
# -- optional '|'
if not check(stream, '|'):
return __debug_exit(result, stream)
position_1 = stream.tell()
__debug_print("'|' (in expression)")
# -- expression
result_2 = snap_expression(stream, PatternDict)
__debug_print("expression(in expression):", result_2)
if result_2 == None:
stream.seek(position_1)
return __debug_exit(result, stream)
result = parallelize.do([result, result_2])
return __debug_exit(construct.beautify(result), stream)
def snap_primary(stream, PatternDict):
"""primary: " non_double_quote * " = character string
[ non_rect_bracket_close ] = set of characters
{ identifier } = pattern replacement
( expression )
non_control_character+ = lonely characters
primary repetition_cmd
"""
__debug_entry("primary", stream)
x = stream.read(1)
lookahead = stream.read(1)
if x != "" and lookahead != "": stream.seek(-1, 1)
if x == "": return __debug_exit(None, stream)
# -- 'primary' primary
if x == "\"": result = snap_character_string.do(stream)
elif x == "[":
stream.seek(-1, 1)
result = character_set_expression.do(stream, PatternDict)
elif x == "{":
result = snap_replacement(stream, PatternDict)
elif x == ".":
result = create_ALL_BUT_NEWLINE_state_machine()
elif x == "(":
result = snap_bracketed_expression(stream, PatternDict)
elif x.isspace():
# a lonestanding space ends the regular expression
stream.seek(-1, 1)
return __debug_exit(None, stream)
elif x in ["*", "+", "?"]:
raise RegularExpressionException(
"lonely operator '%s' without expression proceeding." % x)
elif x == "\\":
if lookahead == "C":
stream.read(1)
result = snap_case_folded_pattern(stream, PatternDict)
else:
stream.seek(-1, 1)
trigger_set = character_set_expression.snap_property_set(stream)
if trigger_set == None:
stream.seek(
1, 1) # snap_property_set() leaves tream right before '\\'
char_code = snap_backslashed_character.do(stream)
if char_code == None:
raise RegularExpressionException(
"Backslash followed by unrecognized character code.")
trigger_set = char_code
result = StateMachine()
result.add_transition(result.init_state_index,
trigger_set,
AcceptanceF=True)
elif x not in CONTROL_CHARACTERS:
# NOTE: The '\' is not inside the control characters---for a reason.
# It is used to define for example character codes using '\x' etc.
stream.seek(-1, 1)
result = snap_non_control_character(stream, PatternDict)
else:
# NOTE: This includes the '$' sign which means 'end of line'
# because the '$' sign is in CONTROL_CHARACTERS, but is not checked
# against. Thus, it it good to leave here on '$' because the
# '$' sign is handled on the very top level.
# this is not a valid primary
stream.seek(-1, 1)
return __debug_exit(None, stream)
# -- optional repetition command?
result_repeated = __snap_repetition_range(result, stream)
## print "##imr:", result.get_string(NormalizeF=False)
if result_repeated != None: result = result_repeated
return __debug_exit(construct.beautify(result), stream)
