def parse_section(fh, Setup):
# NOTE: End of File is supposed to be reached when trying to read a new
# section. Thus, the end-of-file catcher does not encompass the beginning.
position = fh.tell()
skip_whitespace(fh)
word = read_next_word(fh)
try:
# (*) determine what is defined
#
# -- 'mode { ... }' => define a mode
# -- 'start = ...;' => define the name of the initial mode
# -- 'header { ... }' => define code that is to be pasted on top
# of the engine (e.g. "#include<...>")
# -- 'body { ... }' => define code that is to be pasted in the class' body
# of the engine (e.g. "public: int my_member;")
# -- 'init { ... }' => define code that is to be pasted in the class' constructors
# of the engine (e.g. "my_member = -1;")
# -- 'define { ... }' => define patterns shorthands such as IDENTIFIER for [a-z]+
# -- 'token { ... }' => define token ids
#
if word == "start":
parse_initial_mode_definition(fh)
return
elif word == "header":
fragment = code_fragment.parse(fh, "header", AllowBriefTokenSenderF=False)
lexer_mode.header = fragment
return
elif word == "body":
fragment = code_fragment.parse(fh, "body", AllowBriefTokenSenderF=False)
lexer_mode.class_body = fragment
return
elif word == "init":
fragment = code_fragment.parse(fh, "init", AllowBriefTokenSenderF=False)
lexer_mode.class_init = fragment
return
elif word == "define":
parse_pattern_name_definitions(fh, Setup)
return
elif word == "token":
parse_token_id_definitions(fh, Setup)
return
elif word == "mode":
mode_definition.parse(fh, Setup)
return
else:
error_msg("sequence '%s' not recognized as valid keyword in this context\n" % word + \
"use: 'mode', 'header', 'body', 'init', 'define', 'token' or 'start'", fh)
except EndOfStreamException:
fh.seek(position)
error_msg("End of file reached while parsing '%s' section" % word, fh)
def check_for_event_specification(word, fh, new_mode):
pos = fh.tell()
# Allow '<<EOF>>' and '<<FAIL>>' out of respect for classical tools like 'lex'
if word == "<<EOF>>": word = "on_end_of_stream"
elif word == "<<FAIL>>": word = "on_failure"
elif len(word) < 3 or word[:3] != "on_": return False
comment = "Unknown event handler '%s'. \n" % word + \
"Note, that any pattern starting with 'on_' is considered an event handler.\n" + \
"use double quotes to bracket patterns that start with 'on_'."
__general_validate(fh, new_mode, word, pos)
verify_word_in_list(word, lexer_mode.event_handler_db.keys(), comment, fh)
__validate_required_token_policy_queue(word, fh, pos)
continue_f = True
if word == "on_end_of_stream":
# When a termination token is sent, no other token shall follow.
# => Enforce return from the analyzer! Do not allow CONTINUE!
continue_f = False
new_mode.events[word] = code_fragment.parse(fh,
"%s::%s event handler" %
(new_mode.name, word),
ContinueF=continue_f)
return True
def check_for_event_specification(word, fh, new_mode):
pos = fh.tell()
# Allow '<<EOF>>' and '<<FAIL>>' out of respect for classical tools like 'lex'
if word == "<<EOF>>": word = "on_end_of_stream"
elif word == "<<FAIL>>": word = "on_failure"
elif len(word) < 3 or word[:3] != "on_": return False
comment = "Unknown event handler '%s'. \n" % word + \
"Note, that any pattern starting with 'on_' is considered an event handler.\n" + \
"use double quotes to bracket patterns that start with 'on_'."
__general_validate(fh, new_mode, word, pos)
verify_word_in_list(word, lexer_mode.event_handler_db.keys(), comment, fh)
__validate_required_token_policy_queue(word, fh, pos)
continue_f = True
if word == "on_end_of_stream":
# When a termination token is sent, no other token shall follow.
# => Enforce return from the analyzer! Do not allow CONTINUE!
continue_f = False
new_mode.events[word] = code_fragment.parse(fh, "%s::%s event handler" % (new_mode.name, word),
ContinueF=continue_f)
return True
def __parse_section(fh, descriptor, already_defined_list):
global token_type_code_fragment_db
assert type(already_defined_list) == list
SubsectionList = ["name", "file_name", "standard", "distinct", "union", "inheritable", "noid"] \
+ token_type_code_fragment_db.keys()
position = fh.tell()
skip_whitespace(fh)
word = read_identifier(fh)
if word == "":
fh.seek(position)
if check(fh, "}"):
fh.seek(position)
return False
error_msg("Missing token_type section ('standard', 'distinct', or 'union').", fh)
verify_word_in_list(word, SubsectionList,
"Subsection '%s' not allowed in token_type section." % word, fh)
if word == "name":
if not check(fh, "="):
error_msg("Missing '=' in token_type 'name' specification.", fh)
descriptor.class_name, descriptor.name_space, descriptor.class_name_safe = read_namespaced_name(fh, "token_type")
if not check(fh, ";"):
error_msg("Missing terminating ';' in token_type 'name' specification.", fh)
elif word == "inheritable":
descriptor.open_for_derivation_f = True
check_or_quit(fh, ";")
elif word == "noid":
descriptor.token_contains_token_id_f = False;
check_or_quit(fh, ";")
elif word == "file_name":
if not check(fh, "="):
error_msg("Missing '=' in token_type 'file_name' specification.", fh)
descriptor.set_file_name(read_until_letter(fh, ";"))
if not check(fh, ";"):
error_msg("Missing terminating ';' in token_type 'file_name' specification.", fh)
elif word in ["standard", "distinct", "union"]:
if word == "standard": parse_standard_members(fh, descriptor, already_defined_list)
elif word == "distinct": parse_distinct_members(fh, descriptor, already_defined_list)
elif word == "union": parse_union_members(fh, descriptor, already_defined_list)
if not check(fh, "}"):
fh.seek(position)
error_msg("Missing closing '}' at end of token_type section '%s'." % word, fh);
elif word in token_type_code_fragment_db.keys():
fragment = code_fragment.parse(fh, word, AllowBriefTokenSenderF=False)
descriptor.__dict__[word] = fragment
else:
assert False, "This code section section should not be reachable because 'word'\n" + \
"was checked to fit in one of the 'elif' cases."
return True
def parse_action_code(new_mode, fh, pattern, pattern_state_machine):
position = fh.tell()
try:
skip_whitespace(fh)
position = fh.tell()
code_obj = code_fragment.parse(fh,
"regular expression",
ErrorOnFailureF=False)
if code_obj != None:
new_mode.add_match(pattern, code_obj, pattern_state_machine)
return
fh.seek(position)
word = read_until_letter(fh, [";"])
if word == "PRIORITY-MARK":
# This mark 'lowers' the priority of a pattern to the priority of the current
# pattern index (important for inherited patterns, that have higher precedence).
# The parser already constructed a state machine for the pattern that is to
# be assigned a new priority. Since, this machine is not used, let us just
# use its id.
fh.seek(-1, 1)
check_or_quit(fh, ";",
". Since quex version 0.33.5 this is required.")
new_mode.add_match_priority(pattern, pattern_state_machine,
pattern_state_machine.get_id(),
fh.name,
get_current_line_info_number(fh))
elif word == "DELETION":
# This mark deletes any pattern that was inherited with the same 'name'
fh.seek(-1, 1)
check_or_quit(fh, ";",
". Since quex version 0.33.5 this is required.")
new_mode.add_match_deletion(pattern, pattern_state_machine,
fh.name,
get_current_line_info_number(fh))
else:
error_msg("Missing token '{', 'PRIORITY-MARK', 'DELETION', or '=>' after '%s'.\n" % pattern + \
"found: '%s'. Note, that since quex version 0.33.5 it is required to add a ';'\n" % word + \
"to the commands PRIORITY-MARK and DELETION.", fh)
except EndOfStreamException:
fh.seek(position)
error_msg("End of file reached while parsing action code for pattern.",
fh)
def check_for_event_specification(word, fh, new_mode):
if word == "on_entry":
# Event: enter into mode
new_mode.on_entry = code_fragment.parse(
fh, "%s::on_entry event handler" % new_mode.name)
return True
elif word == "on_exit":
# Event: exit from mode
new_mode.on_exit = code_fragment.parse(
fh, "%s::on_exit event handler" % new_mode.name)
return True
elif word == "on_match":
# Event: exit from mode
new_mode.on_match = code_fragment.parse(
fh, "%s::on_match event handler" % new_mode.name)
return True
elif word == "on_indentation":
# Event: start of indentation,
# first non-whitespace after whitespace
new_mode.on_indentation = code_fragment.parse(
fh, "%s::on_indentation event handler" % new_mode.name)
return True
elif word == "on_failure" or word == "<<FAIL>>":
# Event: No pattern matched for current position.
# NOTE: See 'on_end_of_stream' comments.
new_mode.on_failure = code_fragment.parse(
fh, "%s::on_failure event handler" % new_mode.name)
return True
elif word == "on_end_of_stream" or word == "<<EOF>>":
# Event: End of data stream / end of file
# NOTE: The regular expression parser relies on <<EOF>> and <<FAIL>>. So those
# patterns are entered here, even if later versions of quex might dismiss
# those rule deefinitions in favor of consistent event handlers.
new_mode.on_end_of_stream = code_fragment.parse(
fh, "%s::on_end_of_stream event handler" % new_mode.name)
return True
elif len(word) >= 3 and word[:3] == "on_":
error_msg("Unknown event handler '%s'. Known event handlers are:\n\n" % word + \
"on_entry, on_exit, on_indentation, on_end_of_stream, on_failure. on_match\n\n" + \
"Note, that any pattern starting with 'on_' is considered an event handler.\n" + \
"use double quotes to bracket patterns that start with 'on_'.", fh)
# word was not an event specification
return False
def parse_action_code(new_mode, fh, pattern, pattern_state_machine):
position = fh.tell()
try:
skip_whitespace(fh)
position = fh.tell()
code_obj = code_fragment.parse(fh, "regular expression", ErrorOnFailureF=False)
if code_obj != None:
new_mode.add_match(pattern, code_obj, pattern_state_machine)
return
fh.seek(position)
word = read_until_letter(fh, [";"])
if word == "PRIORITY-MARK":
# This mark 'lowers' the priority of a pattern to the priority of the current
# pattern index (important for inherited patterns, that have higher precedence).
# The parser already constructed a state machine for the pattern that is to
# be assigned a new priority. Since, this machine is not used, let us just
# use its id.
fh.seek(-1, 1)
check_or_quit(fh, ";", ". Since quex version 0.33.5 this is required.")
new_mode.add_match_priority(pattern, pattern_state_machine, pattern_state_machine.get_id(),
fh.name, get_current_line_info_number(fh))
elif word == "DELETION":
# This mark deletes any pattern that was inherited with the same 'name'
fh.seek(-1, 1)
check_or_quit(fh, ";", ". Since quex version 0.33.5 this is required.")
new_mode.add_match_deletion(pattern, pattern_state_machine, fh.name, get_current_line_info_number(fh))
else:
error_msg("Missing token '{', 'PRIORITY-MARK', 'DELETION', or '=>' after '%s'.\n" % pattern + \
"found: '%s'. Note, that since quex version 0.33.5 it is required to add a ';'\n" % word + \
"to the commands PRIORITY-MARK and DELETION.", fh)
except EndOfStreamException:
fh.seek(position)
error_msg("End of file reached while parsing action code for pattern.", fh)
def check_for_event_specification(word, fh, new_mode):
if word == "on_entry":
# Event: enter into mode
new_mode.on_entry = code_fragment.parse(fh, "%s::on_entry event handler" % new_mode.name)
return True
elif word == "on_exit":
# Event: exit from mode
new_mode.on_exit = code_fragment.parse(fh, "%s::on_exit event handler" % new_mode.name)
return True
elif word == "on_match":
# Event: exit from mode
new_mode.on_match = code_fragment.parse(fh, "%s::on_match event handler" % new_mode.name)
return True
elif word == "on_indentation":
# Event: start of indentation,
# first non-whitespace after whitespace
new_mode.on_indentation = code_fragment.parse(fh, "%s::on_indentation event handler" % new_mode.name)
return True
elif word == "on_failure" or word == "<<FAIL>>":
# Event: No pattern matched for current position.
# NOTE: See 'on_end_of_stream' comments.
new_mode.on_failure = code_fragment.parse(fh, "%s::on_failure event handler" % new_mode.name)
return True
elif word == "on_end_of_stream" or word == "<<EOF>>":
# Event: End of data stream / end of file
# NOTE: The regular expression parser relies on <<EOF>> and <<FAIL>>. So those
# patterns are entered here, even if later versions of quex might dismiss
# those rule deefinitions in favor of consistent event handlers.
new_mode.on_end_of_stream = code_fragment.parse(fh, "%s::on_end_of_stream event handler" % new_mode.name)
return True
elif len(word) >= 3 and word[:3] == "on_":
error_msg("Unknown event handler '%s'. Known event handlers are:\n\n" % word + \
"on_entry, on_exit, on_indentation, on_end_of_stream, on_failure. on_match\n\n" + \
"Note, that any pattern starting with 'on_' is considered an event handler.\n" + \
"use double quotes to bracket patterns that start with 'on_'.", fh)
# word was not an event specification
return False
def __parse_section(fh, descriptor, already_defined_list):
global token_type_code_fragment_db
assert type(already_defined_list) == list
SubsectionList = ["name", "file_name", "standard", "distinct", "union", "inheritable", "noid"] \
+ token_type_code_fragment_db.keys()
position = fh.tell()
skip_whitespace(fh)
word = read_identifier(fh)
if word == "":
fh.seek(position)
if check(fh, "}"):
fh.seek(position)
return False
error_msg(
"Missing token_type section ('standard', 'distinct', or 'union').",
fh)
verify_word_in_list(
word, SubsectionList,
"Subsection '%s' not allowed in token_type section." % word, fh)
if word == "name":
if not check(fh, "="):
error_msg("Missing '=' in token_type 'name' specification.", fh)
descriptor.class_name, descriptor.name_space, descriptor.class_name_safe = read_namespaced_name(
fh, "token_type")
if not check(fh, ";"):
error_msg(
"Missing terminating ';' in token_type 'name' specification.",
fh)
elif word == "inheritable":
descriptor.open_for_derivation_f = True
check_or_quit(fh, ";")
elif word == "noid":
descriptor.token_contains_token_id_f = False
check_or_quit(fh, ";")
elif word == "file_name":
if not check(fh, "="):
error_msg("Missing '=' in token_type 'file_name' specification.",
fh)
descriptor.set_file_name(read_until_letter(fh, ";"))
if not check(fh, ";"):
error_msg(
"Missing terminating ';' in token_type 'file_name' specification.",
fh)
elif word in ["standard", "distinct", "union"]:
if word == "standard":
parse_standard_members(fh, descriptor, already_defined_list)
elif word == "distinct":
parse_distinct_members(fh, descriptor, already_defined_list)
elif word == "union":
parse_union_members(fh, descriptor, already_defined_list)
if not check(fh, "}"):
fh.seek(position)
error_msg(
"Missing closing '}' at end of token_type section '%s'." %
word, fh)
elif word in token_type_code_fragment_db.keys():
fragment = code_fragment.parse(fh, word, AllowBriefTokenSenderF=False)
descriptor.__dict__[word] = fragment
else:
assert False, "This code section section should not be reachable because 'word'\n" + \
"was checked to fit in one of the 'elif' cases."
return True
def parse_section(fh, Setup):
# NOTE: End of File is supposed to be reached when trying to read a new
# section. Thus, the end-of-file catcher does not encompass the beginning.
position = fh.tell()
skip_whitespace(fh)
word = read_next_word(fh)
try:
# (*) determine what is defined
#
# -- 'mode { ... }' => define a mode
# -- 'start = ...;' => define the name of the initial mode
# -- 'header { ... }' => define code that is to be pasted on top
# of the engine (e.g. "#include<...>")
# -- 'body { ... }' => define code that is to be pasted in the class' body
# of the engine (e.g. "public: int my_member;")
# -- 'init { ... }' => define code that is to be pasted in the class' constructors
# of the engine (e.g. "my_member = -1;")
# -- 'define { ... }' => define patterns shorthands such as IDENTIFIER for [a-z]+
# -- 'token { ... }' => define token ids
#
if word == "start":
parse_initial_mode_definition(fh)
return
elif word == "header":
fragment = code_fragment.parse(fh,
"header",
AllowBriefTokenSenderF=False)
lexer_mode.header = fragment
return
elif word == "body":
fragment = code_fragment.parse(fh,
"body",
AllowBriefTokenSenderF=False)
lexer_mode.class_body = fragment
return
elif word == "init":
fragment = code_fragment.parse(fh,
"init",
AllowBriefTokenSenderF=False)
lexer_mode.class_init = fragment
return
elif word == "define":
parse_pattern_name_definitions(fh, Setup)
return
elif word == "token":
parse_token_id_definitions(fh, Setup)
return
elif word == "mode":
mode_definition.parse(fh, Setup)
return
else:
error_msg("sequence '%s' not recognized as valid keyword in this context\n" % word + \
"use: 'mode', 'header', 'body', 'init', 'define', 'token' or 'start'", fh)
except EndOfStreamException:
fh.seek(position)
error_msg("End of file reached while parsing '%s' section" % word, fh)
def parse_section(fh):
global default_token_type_definition_triggered_by_mode_definition_f
# NOTE: End of File is supposed to be reached when trying to read a new
# section. Thus, the end-of-file catcher does not encompass the beginning.
position = fh.tell()
skip_whitespace(fh)
word = read_identifier(fh)
if word == "":
error_msg("Missing section title.", fh)
SectionTitleList = ["start", "define", "token", "mode", "repeated_token", "token_type" ] + lexer_mode.fragment_db.keys()
verify_word_in_list(word, SectionTitleList, "Unknown quex section '%s'" % word, fh)
try:
# (*) determine what is defined
#
# -- 'mode { ... }' => define a mode
# -- 'start = ...;' => define the name of the initial mode
# -- 'header { ... }' => define code that is to be pasted on top
# of the engine (e.g. "#include<...>")
# -- 'body { ... }' => define code that is to be pasted in the class' body
# of the engine (e.g. "public: int my_member;")
# -- 'init { ... }' => define code that is to be pasted in the class' constructors
# of the engine (e.g. "my_member = -1;")
# -- 'define { ... }' => define patterns shorthands such as IDENTIFIER for [a-z]+
# -- 'repeated_token_id = QUEX_TKN_ ...;' => enables token repetition, defines
# the token id to be repeated.
# -- 'token { ... }' => define token ids
# -- 'token_type { ... }' => define a customized token type
#
if word in lexer_mode.fragment_db.keys():
element_name = lexer_mode.fragment_db[word]
fragment = code_fragment.parse(fh, word, AllowBriefTokenSenderF=False)
lexer_mode.__dict__[element_name] = fragment
return
elif word == "start":
mode_name = parse_identifier_assignment(fh)
if mode_name == "":
error_msg("Missing mode_name after 'start ='", fh)
elif lexer_mode.initial_mode.get_pure_code() != "":
error_msg("start mode defined more than once!", fh, DontExitF=True)
error_msg("previously defined here",
lexer_mode.initial_mode.filename,
lexer_mode.initial_mode.line_n)
lexer_mode.initial_mode = UserCodeFragment(mode_name, fh.name,
get_current_line_info_number(fh))
return
elif word == "repeated_token":
lexer_mode.token_repetition_token_id_list = parse_token_id_definitions(fh, NamesOnlyF=True)
for token_name in lexer_mode.token_repetition_token_id_list:
verify_word_in_list(token_name[len(Setup.token_id_prefix):],
lexer_mode.token_id_db.keys(),
"Token ID '%s' not yet defined." % token_name,
fh, ExitF=False)
return
elif word == "define":
parse_pattern_name_definitions(fh)
return
elif word == "token":
parse_token_id_definitions(fh)
return
elif word == "token_type":
if Setup.token_class_file != "":
error_msg("Token type definition inadmissible while specifying on the command line\n" + \
"the file %s to contain a manually written token class." % repr(Setup.token_class_file),
fh)
if lexer_mode.token_type_definition == None:
lexer_mode.token_type_definition = token_type_definition.parse(fh)
return
# Error case:
if default_token_type_definition_triggered_by_mode_definition_f:
error_msg("Section 'token_type' must appear before first mode definition.", fh)
else:
error_msg("Section 'token_type' has been defined twice.", fh, DontExitF=True)
error_msg("Previously defined here.",
lexer_mode.token_type_definition.file_name_of_token_type_definition,
lexer_mode.token_type_definition.line_n_of_token_type_definition)
return
elif word == "mode":
# When the first mode is parsed then a token_type definition must be
# present. If not, the default token type definition is considered.
if lexer_mode.token_type_definition == None:
sub_fh = open_file_or_die(os.environ["QUEX_PATH"]
+ Setup.language_db["$code_base"]
+ Setup.language_db["$token-default-file"])
parse_section(sub_fh)
sub_fh.close()
default_token_type_definition_triggered_by_mode_definition_f = True
mode_definition.parse(fh)
return
else:
# This case should have been caught by the 'verify_word_in_list' function
assert False
except EndOfStreamException:
fh.seek(position)
error_msg("End of file reached while parsing '%s' section" % word, fh)
