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extern const char *help;
const char *help =
"\n"
" -? -h --help\n"
" Show help message.\n"
"\n"
" -b --bit-vectors\n"
" Optimize conditional jumps using bit masks. Implies -s.\n"
"\n"
" -c --conditions --start-conditions\n"
" Enable support of Flex-like \"conditions\": multiple interrelated\n"
" lexers within one block. Option --start-conditions is a legacy\n"
" alias; use --conditions instead.\n"
"\n"
" -d --debug-output\n"
" Emit YYDEBUG in the generated code. YYDEBUG should be defined\n"
" by the user in the form of a void function with two parameters:\n"
" state (lexer state or -1) and symbol (current input symbol of\n"
" type YYCTYPE).\n"
"\n"
" -D --emit-dot\n"
" Instead of normal output generate lexer graph in DOT format.\n"
" The output can be converted to PNG with the help of Graphviz\n"
" (something like dot -Tpng -odfa.png dfa.dot). Note that large\n"
" graphs may crash Graphviz.\n"
"\n"
" -e --ecb\n"
" Generate a lexer that reads input in EBCDIC encoding. re2c\n"
" assumes that character range is 0 -- 0xFF an character size is 1\n"
" byte.\n"
"\n"
" -f --storable-state\n"
" Generate a lexer which can store its inner state. This is use‐\n"
" ful in push-model lexers which are stopped by an outer program\n"
" when there is not enough input, and then resumed when more input\n"
" becomes available. In this mode users should additionally\n"
" define YYGETSTATE () and YYSETSTATE (state) macros and variables\n"
" yych, yyaccept and the state as part of the lexer state.\n"
"\n"
" -F --flex-syntax\n"
" Partial support for Flex syntax: in this mode named definitions\n"
" don't need the equal sign and the terminating semicolon, and\n"
" when used they must be surrounded by curly braces. Names with‐\n"
" out curly braces are treated as double-quoted strings.\n"
"\n"
" -g --computed-gotos\n"
" Optimize conditional jumps using non-standard \"computed goto\"\n"
" extension (must be supported by C/C++ compiler). re2c generates\n"
" jump tables only in complex cases with a lot of conditional\n"
" branches. Complexity threshold can be configured with\n"
" cgoto:threshold configuration. This option implies -b.\n"
"\n"
" -i --no-debug-info\n"
" Do not output #line information. This is useful when the gener‐\n"
" ated code is tracked by some version control system.\n"
"\n"
" -o OUTPUT --output=OUTPUT\n"
" Specify the OUTPUT file.\n"
"\n"
" -r --reusable\n"
" Allows reuse of re2c rules with /*!rules:re2c */ and /*!use:re2c\n"
" */ blocks. In this mode simple /*!re2c */ blocks are not\n"
" allowed and exactly one /*!rules:re2c */ block must be present.\n"
" The rules are saved and used by every /*!use:re2c */ block that\n"
" follows (which may add rules of their own). This option allows\n"
" one to reuse the same set of rules with different configurations.\n"
"\n"
" -s --nested-ifs\n"
" Use nested if statements instead of switch statements in condi‐\n"
" tional jumps. This usually results in more efficient code with\n"
" non-optimizing C/C++ compilers.\n"
"\n"
" -t HEADER --type-header=HEADER\n"
" Generate a HEADER file that contains enum with condition names.\n"
" Requires -c option.\n"
"\n"
" -T --tags\n"
" Enable submatch extraction with tags.\n"
"\n"
" -P --posix-captures\n"
" Enable submatch extraction with POSIX-style capturing groups.\n"
"\n"
" -u --unicode\n"
" Generate a lexer that reads input in UTF-32 encoding. re2c\n"
" assumes that character range is 0 -- 0x10FFFF and character size\n"
" is 4 bytes. Implies -s.\n"
"\n"
" -v --version\n"
" Show version information.\n"
"\n"
" -V --vernum\n"
" Show version information in MMmmpp format (major, minor, patch).\n"
"\n"
" -w --wide-chars\n"
" Generate a lexer that reads input in UCS-2 encoding. re2c\n"
" assumes that character range is 0 -- 0xFFFF and character size\n"
" is 2 bytes. Implies -s.\n"
"\n"
" -x --utf-16\n"
" Generate a lexer that reads input in UTF-16 encoding. re2c\n"
" assumes that character range is 0 -- 0x10FFFF and character size\n"
" is 2 bytes. Implies -s.\n"
"\n"
" -8 --utf-8\n"
" Generate a lexer that reads input in UTF-8 encoding. re2c\n"
" assumes that character range is 0 -- 0x10FFFF and character size\n"
" is 1 byte.\n"
"\n"
" --case-insensitive\n"
" Treat single-quoted and double-quoted strings as case-insensi‐\n"
" tive.\n"
"\n"
" --case-inverted\n"
" Invert the meaning of single-quoted and double-quoted strings:\n"
" treat single-quoted strings as case-sensitive and double-quoted\n"
" strings as case-insensitive.\n"
"\n"
" --no-generation-date\n"
" Suppress date output in the generated file.\n"
"\n"
" --no-lookahead\n"
" Use TDFA(0) instead of TDFA(1). This option only has effect\n"
" with --tags or --posix-captures options.\n"
"\n"
" --no-optimize-tags\n"
" Suppress optimization of tag variables (useful for debugging or\n"
" benchmarking).\n"
"\n"
" --no-version\n"
" Suppress version output in the generated file.\n"
"\n"
" --encoding-policy POLICY\n"
" Define the way re2c treats Unicode surrogates. POLICY can be\n"
" one of the following: fail (abort with an error when a surrogate\n"
" is encountered), substitute (silently replace surrogates with\n"
" the error code point 0xFFFD), ignore (default, treat surrogates\n"
" as normal code points). The Unicode standard says that stand‐\n"
" alone surrogates are invalid, but real-world libraries and pro‐\n"
" grams behave in different ways.\n"
"\n"
" --input INPUT\n"
" Specify re2c input API. INPUT can be either default or custom\n"
" (enables the use of generic API).\n"
"\n"
" -S --skeleton\n"
" Ignore user-defined interface code and generate a self-contained\n"
" \"skeleton\" program. Additionally, generate input files with\n"
" strings derived from the regular grammar and compressed match\n"
" results that are used to verify \"skeleton\" behavior on all\n"
" inputs. This option is useful for finding bugs in optimizations\n"
" and code generation.\n"
"\n"
" --empty-class POLICY\n"
" Define the way re2c treats empty character classes. POLICY can\n"
" be one of the following: match-empty (match empty input: illogi‐\n"
" cal, but default behavior for backwards compatibility reasons),\n"
" match-none (fail to match on any input), error (compilation\n"
" error).\n"
"\n"
" --dfa-minimization ALGORITHM\n"
" The internal algorithm used by re2c to minimize the DFA. ALGO‐\n"
" RITHM can be either moore (Moore algorithm, the default) or ta‐\n"
" ble (table filling algorithm). Both algorithms should produce\n"
" the same DFA up to states relabeling; table filling is much\n"
" slower and serves as a reference implementation.\n"
"\n"
" --eager-skip\n"
" Make the generated lexer advance the input position \"eagerly\":\n"
" immediately after reading input symbol. By default this happens\n"
" after transition to the next state. Implied by --no-lookahead.\n"
"\n"
" --dump-nfa\n"
" Generate representation of NFA in DOT format and dump it on\n"
" stderr.\n"
"\n"
" --dump-dfa-raw\n"
" Generate representation of DFA in DOT format under construction\n"
" and dump it on stderr.\n"
"\n"
" --dump-dfa-det\n"
" Generate representation of DFA in DOT format immediately after\n"
" determinization and dump it on stderr.\n"
"\n"
" --dump-dfa-tagopt\n"
" Generate representation of DFA in DOT format after tag optimiza‐\n"
" tions and dump it on stderr.\n"
"\n"
" --dump-dfa-min\n"
" Generate representation of DFA in DOT format after minimization\n"
" and dump it on stderr.\n"
"\n"
" --dump-adfa\n"
" Generate representation of DFA in DOT format after tunneling and\n"
" dump it on stderr.\n"
"\n"
" -1 --single-pass\n"
" Deprecated. Does nothing (single pass is the default now).\n"
"\n"
" -W Turn on all warnings.\n"
"\n"
" -Werror\n"
" Turn warnings into errors. Note that this option alone doesn't\n"
" turn on any warnings; it only affects those warnings that have\n"
" been turned on so far or will be turned on later.\n"
"\n"
" -W<warning>\n"
" Turn on warning.\n"
"\n"
" -Wno-<warning>\n"
" Turn off warning.\n"
"\n"
" -Werror-<warning>\n"
" Turn on warning and treat it as an error (this implies -W<warn‐\n"
" ing>).\n"
"\n"
" -Wno-error-<warning>\n"
" Don't treat this particular warning as an error. This doesn't\n"
" turn off the warning itself.\n"
"\n"
" -Wcondition-order\n"
" Warn if the generated program makes implicit assumptions about\n"
" condition numbering. One should use either the -t, --type-header\n"
" option or the /*!types:re2c*/ directive to generate a mapping of\n"
" condition names to numbers and then use the autogenerated condi‐\n"
" tion names.\n"
"\n"
" -Wempty-character-class\n"
" Warn if a regular expression contains an empty character class.\n"
" Trying to match an empty character class makes no sense: it\n"
" should always fail. However, for backwards compatibility rea‐\n"
" sons re2c allows empty character classes and treats them as\n"
" empty strings. Use the --empty-class option to change the\n"
" default behavior.\n"
"\n"
" -Wmatch-empty-string\n"
" Warn if a rule is nullable (matches an empty string). If the\n"
" lexer runs in a loop and the empty match is unintentional, the\n"
" lexer may unexpectedly hang in an infinite loop.\n"
"\n"
" -Wswapped-range\n"
" Warn if the lower bound of a range is greater than its upper\n"
" bound. The default behavior is to silently swap the range\n"
" bounds.\n"
"\n"
" -Wundefined-control-flow\n"
" Warn if some input strings cause undefined control flow in the\n"
" lexer (the faulty patterns are reported). This is the most dan‐\n"
" gerous and most common mistake. It can be easily fixed by adding\n"
" the default rule * which has the lowest priority, matches any\n"
" code unit, and consumes exactly one code unit.\n"
"\n"
" -Wunreachable-rules\n"
" Warn about rules that are shadowed by other rules and will never\n"
" match.\n"
"\n"
" -Wuseless-escape\n"
" Warn if a symbol is escaped when it shouldn't be. By default,\n"
" re2c silently ignores such escapes, but this may as well indi‐\n"
" cate a typo or an error in the escape sequence.\n"
"\n"
" -Wnondeterministic-tags\n"
" Warn if a tag has n-th degree of nondeterminism, where n is\n"
" greater than 1.\n"
"\n"
;
|
