#!/bin/sh
-sphinx-build -b html src obj
-
-runhaskell launch.hs
+[ -d master ] || {
+ git worktree prune
+ git worktree add master master
+}
+[ -e src/manual/options/options.rst_ ] || #merge manual tree from master
+ (cd master/re2c/doc/; tar cf - manual/) | (cd src/; tar xfp -)
+sphinx-build -b html src obj
+[ $# != 0 ] || #pass an argument to prevent the server from launching
+ runhaskell launch.hs
.. toctree::
:hidden:
-
-You can precede regular expressions with a list of condition names when
-using the ``-c`` switch. ``re2c`` will then generate a scanner block for
-each condition, and each of the generated blocks will have its own
-precondition. The precondition is given by the interface define
-``YYGETCONDITON()`` and must be of type ``YYCONDTYPE``.
-
-There are two special rule types. First, the rules of the condition ``<*>``
-are merged to all conditions (note that they have a lower priority than
-other rules of that condition). And second, the empty condition list
-allows to provide a code block that does not have a scanner part,
-meaning it does not allow any regular expressions. The condition value
-referring to this special block is always the one with the enumeration
-value 0. This way the code of this special rule can be used to
-initialize a scanner. It is in no way necessary to have these rules: but
-sometimes it is helpful to have a dedicated uninitialized condition
-state.
-
-Non empty rules allow to specify the new condition, which makes them
-transition rules. Besides generating calls for the
-``YYSETCONDTITION`` define, no other special code is generated.
-
-There is another kind of special rule that allows to prepend code to any
-code block of all rules of a certain set of conditions or to all code
-blocks of all rules. This can be helpful when some operation is common
-among rules. For instance, this can be used to store the length of the
-scanned string. These special setup rules start with an exclamation mark
-followed by either a list of conditions ``<! condition, ... >`` or a star
-``<!*>``. When ``re2c`` generates the code for a rule whose state does not have a
-setup rule and a starred setup rule is present, the starred setup code will be
-used as setup code.
-
+.. include:: conditions.rst_
.. toctree::
:hidden:
-``re2c`` supports the following encodings: ASCII (default), EBCDIC (``-e``),
-UCS-2 (``-w``), UTF-16 (``-x``), UTF-32 (``-u``) and UTF-8 (``-8``).
-See also inplace configuration ``re2c:flags``.
-
-The following concepts should be clarified when talking about encodings.
-A *code point* is an abstract number that represents a single symbol.
-A *code unit* is the smallest unit of memory, which is used in the
-encoded text (it corresponds to one character in the input stream). One
-or more code units may be needed to represent a single code point,
-depending on the encoding. In a *fixed-length* encoding, each code point
-is represented with an equal number of code units. In *variable-length*
-encodings, different code points can be represented with different number
-of code units.
-
-* ASCII is a fixed-length encoding. Its code space includes 0x100
- code points, from 0 to 0xFF. A code point is represented with exactly one
- 1-byte code unit, which has the same value as the code point. The size of
- ``YYCTYPE`` must be 1 byte.
-
-* EBCDIC is a fixed-length encoding. Its code space includes 0x100
- code points, from 0 to 0xFF. A code point is represented with exactly
- one 1-byte code unit, which has the same value as the code point. The size
- of ``YYCTYPE`` must be 1 byte.
-
-* UCS-2 is a fixed-length encoding. Its code space includes 0x10000
- code points, from 0 to 0xFFFF. One code point is represented with
- exactly one 2-byte code unit, which has the same value as the code
- point. The size of ``YYCTYPE`` must be 2 bytes.
-
-* UTF-16 is a variable-length encoding. Its code space includes all
- Unicode code points, from 0 to 0xD7FF and from 0xE000 to 0x10FFFF. One
- code point is represented with one or two 2-byte code units. The size of
- ``YYCTYPE`` must be 2 bytes.
-
-* UTF-32 is a fixed-length encoding. Its code space includes all
- Unicode code points, from 0 to 0xD7FF and from 0xE000 to 0x10FFFF. One
- code point is represented with exactly one 4-byte code unit. The size of
- ``YYCTYPE`` must be 4 bytes.
-
-* UTF-8 is a variable-length encoding. Its code space includes all
- Unicode code points, from 0 to 0xD7FF and from 0xE000 to 0x10FFFF. One
- code point is represented with a sequence of one, two, three, or four
- 1-byte code units. The size of ``YYCTYPE`` must be 1 byte.
-
-In Unicode, values from range 0xD800 to 0xDFFF (surrogates) are not
-valid Unicode code points. Any encoded sequence of code units that
-would map to Unicode code points in the range 0xD800-0xDFFF, is
-ill-formed. The user can control how ``re2c`` treats such ill-formed
-sequences with the ``--encoding-policy <policy>`` switch.
-
-For some encodings, there are code units that never occur in a valid
-encoded stream (e.g., 0xFF byte in UTF-8). If the generated scanner must
-check for invalid input, the only correct way to do so is to use the default
-rule (``*``). Note that the full range rule (``[^]``) won't catch invalid code units when a variable-length encoding is used
-(``[^]`` means "any valid code point", whereas the default rule (``*``) means "any possible code unit").
+.. include:: encodings.rst_
.. toctree::
:hidden:
-``re2c`` usually operates on input with pointer-like primitives
-``YYCURSOR``, ``YYMARKER``, ``YYCTXMARKER``, and ``YYLIMIT``.
-
-The generic input API (enabled with the ``--input custom`` switch) allows
-customizing input operations. In this mode, ``re2c`` will express all
-operations on input in terms of the following primitives:
-
- +---------------------+-----------------------------------------------------+
- | ``YYPEEK ()`` | get current input character |
- +---------------------+-----------------------------------------------------+
- | ``YYSKIP ()`` | advance to next character |
- +---------------------+-----------------------------------------------------+
- | ``YYBACKUP ()`` | back up current input position |
- +---------------------+-----------------------------------------------------+
- | ``YYBACKUPCTX ()`` | back up current input position for trailing context |
- +---------------------+-----------------------------------------------------+
- | ``YYRESTORE ()`` | restore current input position |
- +---------------------+-----------------------------------------------------+
- | ``YYRESTORECTX ()`` | restore current input position for trailing context |
- +---------------------+-----------------------------------------------------+
- | ``YYLESSTHAN (n)`` | check if less than ``n`` input characters are left |
- +---------------------+-----------------------------------------------------+
+.. include:: generic_api.rst_
This `article <http://skvadrik.github.io/aleph_null/posts/re2c/2015-01-13-input_model.html>`_
has more details, and you can find some usage examples
`here <http://skvadrik.github.io/aleph_null/posts/re2c/2015-01-15-input_model_custom.html>`_.
-
.. toctree::
:hidden:
-
-When the ``-f`` flag is specified, ``re2c`` generates a scanner that can
-store its current state, return to its caller, and later resume
-operations exactly where it left off.
-
-The default mode of operation in ``re2c`` is a
-"pull" model, where the scanner asks for extra input whenever it needs it. However, this mode of operation assumes that the scanner is the "owner" of the parsing loop, and that may not always be convenient.
-
-Typically, if there is a preprocessor ahead of the scanner in the
-stream, or for that matter, any other procedural source of data, the
-scanner cannot "ask" for more data unless both the scanner and the source
-live in separate threads.
-
-The ``-f`` flag is useful exactly for situations like that: it lets users design
-scanners that work in a "push" model, i.e., a model where data is fed to the
-scanner chunk by chunk. When the scanner runs out of data to consume, it
-stores its state and returns to the caller. When more input data is
-fed to the scanner, it resumes operations exactly where it left off.
-
-Changes needed compared to the "pull" model:
-
-* The user has to supply macros named ``YYSETSTATE ()`` and ``YYGETSTATE (state)``.
-
-* The ``-f`` option inhibits declaration of ``yych`` and ``yyaccept``, so the
- user has to declare them and save and restore them where required.
- In the ``examples/push_model/push.re`` example, these are declared as
- fields of a (C++) class of which the scanner is a method, so they do
- not need to be saved/restored explicitly. For C, they could, e.g., be made
- macros that select fields from a structure passed in as a parameter.
- Alternatively, they could be declared as local variables, saved with
- ``YYFILL (n)`` when it decides to return and restored upon entering the
- function. Also, it could be more efficient to save the state from
- ``YYFILL (n)`` because ``YYSETSTATE (state)`` is called unconditionally.
- ``YYFILL (n)`` however does not get ``state`` as a parameter, so we would have
- to store state in a local variable by ``YYSETSTATE (state)``.
-
-* Modify ``YYFILL (n)`` to return (from the function calling it) if more input is needed.
-
-* Modify the caller to recognize if more input is needed and respond appropriately.
-
-* The generated code will contain a switch block that is used to
- restore the last state by jumping behind the corresponding ``YYFILL (n)``
- call. This code is automatically generated in the epilogue of the first ``/*!re2c */``
- block. It is possible to trigger generation of the ``YYGETSTATE ()``
- block earlier by placing a ``/*!getstate:re2c*/`` comment. This is especially useful when the scanner code should be
- wrapped inside a loop.
-
-Please see ``examples/push_model/push.re`` for an example of a "push" model scanner. The
-generated code can be tweaked with inplace configurations ``state:abort``
-and ``state:nextlabel``.
+
+.. include:: state.rst_
+++ /dev/null
-``-? -h --help``
- Show a short help screen:
-
-``-b --bit-vectors``
- Implies ``-s``. Use bit vectors as well to try to
- coax better code out of the compiler. Most useful for
- specifications with more than a few keywords (e.g., for most programming
- languages).
-
-``-c --conditions``
- Used for (f)lex-like condition support.
-
-``-d --debug-output``
- Creates a parser that dumps information about
- the current position and the state the parser is in.
- This is useful for debugging parser issues and states. If you use this
- switch, you need to define a ``YYDEBUG`` macro, which will be called like a
- function with two parameters: ``void YYDEBUG (int state, char current)``.
- The first parameter receives the state or ``-1`` and the second parameter
- receives the input at the current cursor.
-
-``-D --emit-dot``
- Emit Graphviz dot data, which can then be processed
- with e.g., ``dot -Tpng input.dot > output.png``. Please note that
- scanners with many states may crash dot.
-
-``-e --ecb``
- Generate a parser that supports EBCDIC. The generated
- code can deal with any character up to 0xFF. In this mode, ``re2c`` assumes
- an input character size of 1 byte. This switch is incompatible with
- ``-w``, ``-x``, ``-u``, and ``-8``.
-
-``-f --storable-state``
- Generate a scanner with support for storable state.
-
-``-F --flex-syntax``
- Partial support for flex syntax. When this flag
- is active, named definitions must be surrounded by curly braces and
- can be defined without an equal sign and the terminating semicolon.
- Instead, names are treated as direct double quoted strings.
-
-``-g --computed-gotos``
- Generate a scanner that utilizes GCC's
- computed-goto feature. That is, ``re2c`` generates jump tables whenever a
- decision is of certain complexity (e.g., a lot of if conditions would be
- otherwise necessary). This is only usable with compilers that support this feature.
- Note that this implies ``-b`` and that the complexity threshold can be configured
- using the ``cgoto:threshold`` inplace configuration.
-
-``-i --no-debug-info``
- Do not output ``#line`` information. This is
- useful when you want use a CMS tool with ``re2c``'s output. You might
- want to do this if you do not want to impose re2c as a build requirement
- for your source.
-
-``-o OUTPUT --output=OUTPUT``
- Specify the ``OUTPUT`` file.
-
-``-r --reusable``
- Allows reuse of scanner definitions with ``/*!use:re2c */`` after ``/*!rules:re2c */``.
- In this mode, no ``/*!re2c */`` block and exactly one ``/*!rules:re2c */`` must be present.
- The rules are saved and used by every ``/*!use:re2c */`` block that follows.
- These blocks can contain inplace configurations, especially ``re2c:flags:e``,
- ``re2c:flags:w``, ``re2c:flags:x``, ``re2c:flags:u``, and ``re2c:flags:8``.
- That way it is possible to create the same scanner multiple times for
- different character types, different input mechanisms, or different output mechanisms.
- The ``/*!use:re2c */`` blocks can also contain additional rules that will be appended
- to the set of rules in ``/*!rules:re2c */``.
-
-``-s --nested-ifs``
- Generate nested ifs for some switches. Many
- compilers need this assist to generate better code.
-
-``-t HEADER --type-header=HEADER``
- Create a ``HEADER`` file that
- contains types for the (f)lex-like condition support. This can only be
- activated when ``-c`` is in use.
-
-``-u --unicode``
- Generate a parser that supports UTF-32. The generated
- code can deal with any valid Unicode character up to 0x10FFFF. In this
- mode, ``re2c`` assumes an input character size of 4 bytes. This switch is
- incompatible with ``-e``, ``-w``, ``-x``, and ``-8``. This implies ``-s``.
-
-``-v --version``
- Show version information.
-
-``-V --vernum``
- Show the version as a number in the MMmmpp (Majorm, minor, patch) format.
-
-``-w --wide-chars``
- Generate a parser that supports UCS-2. The
- generated code can deal with any valid Unicode character up to 0xFFFF.
- In this mode, ``re2c`` assumes an input character size of 2 bytes. This
- switch is incompatible with ``-e``, ``-x``, ``-u``, and ``-8``. This implies
- ``-s``.
-
-``-x --utf-16``
- Generate a parser that supports UTF-16. The generated
- code can deal with any valid Unicode character up to 0x10FFFF. In this
- mode, ``re2c`` assumes an input character size of 2 bytes. This switch is
- incompatible with ``-e``, ``-w``, ``-u``, and ``-8``. This implies ``-s``.
-
-``-8 --utf-8``
- Generate a parser that supports UTF-8. The generated
- code can deal with any valid Unicode character up to 0x10FFFF. In this
- mode, ``re2c`` assumes an input character size of 1 byte. This switch is
- incompatible with ``-e``, ``-w``, ``-x``, and ``-u``.
-
-``--case-insensitive``
- Makes all strings case insensitive. This makes
- "-quoted expressions behave as '-quoted expressions.
-
-``--case-inverted``
- Invert the meaning of single and double quoted
- strings. With this switch, single quotes are case sensitive and double
- quotes are case insensitive.
-
-``--no-generation-date``
- Suppress date output in the generated file.
-
-``--no-version``
- Suppress version output in the generated file.
-
-``--no-generation-date``
- Suppress version output in the generated file.
-
-``--encoding-policy POLICY``
- Specify how ``re2c`` must treat Unicode
- surrogates. ``POLICY`` can be one of the following: ``fail`` (abort with
- an error when a surrogate is encountered), ``substitute`` (silently replace
- surrogates with the error code point 0xFFFD), ``ignore`` (treat surrogates as
- normal code points). By default, ``re2c`` ignores surrogates (for backward
- compatibility). The Unicode standard says that standalone surrogates are
- invalid code points, but different libraries and programs treat them
- differently.
-
-``--input INPUT``
- Specify re2c's input API. ``INPUT`` can be either ``default`` or ``custom``.
-
-``-S --skeleton``
- Instead of embedding re2c-generated code into C/C++
- source, generate a self-contained program for the same DFA. Most useful
- for correctness and performance testing.
-
-``--empty-class POLICY``
- What to do if the user uses an empty character
- class. ``POLICY`` can be one of the following: ``match-empty`` (match empty
- input: pretty illogical, but this is the default for backwards
- compatibility reasons), ``match-none`` (fail to match on any input),
- ``error`` (compilation error). Note that there are various ways to
- construct an empty class, e.g., [], [^\\x00-\\xFF],
- [\\x00-\\xFF][\\x00-\\xFF].
-
-``--dfa-minimization <table | moore>``
- The internal algorithm used by re2c to minimize the DFA (defaults to ``moore``).
- Both the table filling algorithm and the Moore algorithm should produce the same DFA (up to states relabeling).
- The table filling algorithm is much simpler and slower; it serves as a reference implementation.
-
-``-1 --single-pass``
- Deprecated. Does nothing (single pass is the default now).
+++ /dev/null
-Configurations
---------------
-
-``re2c:condprefix = yyc;``
- Allows to specify the prefix used for
- condition labels. That is, the text to be prepended to condition labels
- in the generated output file.
-
-
-``re2c:condenumprefix = yyc;``
- Allows to specify the prefix used for
- condition values. That is, the text to be prepended to condition enum
- values in the generated output file.
-
-``re2c:cond:divider = "/* *********************************** */";``
- Allows to customize the divider for condition blocks. You can use ``@@``
- to put the name of the condition or customize the placeholder using
- ``re2c:cond:divider@cond``.
-
-``re2c:cond:divider@cond = @@;``
- Specifies the placeholder that will be
- replaced with the condition name in ``re2c:cond:divider``.
-
-``re2c:cond:goto = "goto @@;";``
- Allows to customize the condition goto statements used with ``:=>`` style rules. You can use ``@@``
- to put the name of the condition or customize the placeholder using
- ``re2c:cond:goto@cond``. You can also change this to ``continue;``, which
- would allow you to continue with the next loop cycle including any code
- between your loop start and your re2c block.
-
-``re2c:cond:goto@cond = @@;``
- Specifies the placeholder that will be replaced with the condition label in ``re2c:cond:goto``.
-
-``re2c:indent:top = 0;``
- Specifies the minimum amount of indentation to
- use. Requires a numeric value greater than or equal to zero.
-
-``re2c:indent:string = "\t";``
- Specifies the string to use for indentation. Requires a string that should
- contain only whitespace unless you need something else for external tools. The easiest
- way to specify spaces is to enclose them in single or double quotes.
- If you do not want any indentation at all, you can simply set this to "".
-
-``re2c:yych:conversion = 0;``
- When this setting is non zero, ``re2c`` automatically generates
- conversion code whenever yych gets read. In this case, the type must be
- defined using ``re2c:define:YYCTYPE``.
-
-``re2c:yych:emit = 1;``
- Set this to zero to suppress the generation of *yych*.
-
-``re2c:yybm:hex = 0;``
- If set to zero, a decimal table will be used. Otherwise, a hexadecimal table will be generated.
-
-``re2c:yyfill:enable = 1;``
- Set this to zero to suppress the generation of ``YYFILL (n)``. When using this, be sure to verify that the generated
- scanner does not read behind the end of your input, allowing such behavior might
- introduce several security issues to your program.
-
-``re2c:yyfill:check = 1;``
- This can be set to 0 to suppress the generations of
- ``YYCURSOR`` and ``YYLIMIT`` based precondition checks. This option is useful when
- ``YYLIMIT + YYMAXFILL`` is always accessible.
-
-``re2c:define:YYFILL = "YYFILL";``
- Define a substitution for ``YYFILL``. Note that by default,
- ``re2c`` generates an argument in parentheses and a semicolon after
- ``YYFILL``. If you need to make ``YYFILL`` an arbitrary statement rather
- than a call, set ``re2c:define:YYFILL:naked`` to a non-zero value and use
- ``re2c:define:YYFILL@len`` to set a placeholder for the formal parameter inside of your ``YYFILL``
- body.
-
-``re2c:define:YYFILL@len = "@@";``
- Any occurrence of this text
- inside of a ``YYFILL`` call will be replaced with the actual argument.
-
-``re2c:yyfill:parameter = 1;``
- Controls the argument in the parentheses that follow ``YYFILL``. If zero, the argument is omitted.
- If non-zero, the argument is generated unless ``re2c:define:YYFILL:naked`` is set to non-zero.
-
-``re2c:define:YYFILL:naked = 0;``
- Controls the argument in the parentheses after ``YYFILL`` and
- the following semicolon. If zero, both the argument and the semicolon are
- omitted. If non-zero, the argument is generated unless
- ``re2c:yyfill:parameter`` is set to zero; the semicolon is generated
- unconditionally.
-
-``re2c:startlabel = 0;``
- If set to a non zero integer, then the start
- label of the next scanner block will be generated even if it isn't used by
- the scanner itself. Otherwise, the normal ``yy0``-like start label is only
- generated if needed. If set to a text value, then a label with that
- text will be generated regardless of whether the normal start label is
- used or not. This setting is reset to 0 after a start label has been generated.
-
-``re2c:labelprefix = "yy";``
- Allows to change the prefix of numbered
- labels. The default is ``yy``. Can be set any string that is valid in
- a label name.
-
-``re2c:state:abort = 0;``
- When not zero and the ``-f`` switch is active, then
- the ``YYGETSTATE`` block will contain a default case that aborts and a -1
- case will be used for initialization.
-
-``re2c:state:nextlabel = 0;``
- Used when ``-f`` is active to control
- whether the ``YYGETSTATE`` block is followed by a ``yyNext:`` label line.
- Instead of using ``yyNext``, you can usually also use configuration
- ``startlabel`` to force a specific start label or default to ``yy0`` as
- a start label. Instead of using a dedicated label, it is often better to
- separate the ``YYGETSTATE`` code from the actual scanner code by placing a
- ``/*!getstate:re2c*/`` comment.
-
-``re2c:cgoto:threshold = 9;``
- When ``-g`` is active, this value specifies
- the complexity threshold that triggers the generation of jump tables rather
- than nested ifs and decision bitfields. The threshold is compared
- against a calculated estimation of ifs needed where every used bitmap
- divides the threshold by 2.
-
-``re2c:yych:conversion = 0;``
- When input uses signed characters and the
- ``-s`` or ``-b`` switches are in effect, re2c allows automatic conversion
- to the unsigned character type that is then necessary for its internal
- single character. When this setting is zero or an empty string, the
- conversion is disabled. If a non zero number is used, the conversion is taken
- from ``YYCTYPE``. If ``YYCTYPE`` is overridden by an inplace configuration setting, that setting is
- is used instead of a ``YYCTYPE`` cast. Otherwise, it will be ``(YYCTYPE)`` and changes to that
- configuration are no longer possible. When this setting is a string, it must contain the casting
- parentheses. Now assuming your input is a ``char *`` buffer and you are using the above mentioned switches, you can set
- ``YYCTYPE`` to ``unsigned char`` and this setting to either 1 or ``(unsigned char)``.
-
-``re2c:define:YYCONDTYPE = "YYCONDTYPE";``
- Enumeration used for condition support with ``-c`` mode.
-
-``re2c:define:YYCTXMARKER = "YYCTXMARKER";``
- Replaces the ``YYCTXMARKER`` placeholder with the specified identifier.
-
-``re2c:define:YYCTYPE = "YYCTYPE";``
- Replaces the ``YYCTYPE`` placeholder with the specified type.
-
-``re2c:define:YYCURSOR = "YYCURSOR";``
- Replaces the ``YYCURSOR`` placeholder with the specified identifier.
-
-``re2c:define:YYDEBUG = "YYDEBUG";``
- Replaces the ``YYDEBUG`` placeholder with the specified identifier.
-
-``re2c:define:YYGETCONDITION = "YYGETCONDITION";``
- Substitution for
- ``YYGETCONDITION``. Note that by default, ``re2c`` generates parentheses after
- ``YYGETCONDITION``. Set ``re2c:define:YYGETCONDITION:naked`` to non-zero to
- omit the parentheses.
-
-``re2c:define:YYGETCONDITION:naked = 0;``
- Controls the parentheses after
- ``YYGETCONDITION``. If zero, the parentheses are omitted. If non-zero, the parentheses are
- generated.
-
-``re2c:define:YYSETCONDITION = "YYSETCONDITION";``
- Substitution for
- ``YYSETCONDITION``. Note that by default, ``re2c`` generates an argument in
- parentheses followed by semicolon after ``YYSETCONDITION``. If you need to make
- ``YYSETCONDITION`` an arbitrary statement rather than a call, set
- ``re2c:define:YYSETCONDITION:naked`` to non-zero and use
- ``re2c:define:YYSETCONDITION@cond`` to denote the formal parameter inside of the
- ``YYSETCONDITION`` body.
-
-``re2c:define:YYSETCONDITION@cond = "@@";``
- Any occurrence of this
- text inside of ``YYSETCONDITION`` will be replaced with the actual
- argument.
-
-``re2c:define:YYSETCONDITION:naked = 0;``
- Controls the argument in parentheses
- and the semicolon after ``YYSETCONDITION``. If zero, both the argument and
- the semicolon are omitted. If non-zero, both the argument and the semicolon are
- generated.
-
-``re2c:define:YYGETSTATE = "YYGETSTATE";``
- Substitution for
- ``YYGETSTATE``. Note that by default, ``re2c`` generates parentheses after
- ``YYGETSTATE``. Set ``re2c:define:YYGETSTATE:naked`` to non-zero to omit
- the parentheses.
-
-``re2c:define:YYGETSTATE:naked = 0;``
- Controls the parentheses that follow
- ``YYGETSTATE``. If zero, the parentheses are omitted. If non-zero, they are
- generated.
-
-``re2c:define:YYSETSTATE = "YYSETSTATE";``
- Substitution for
- ``YYSETSTATE``. Note that by default, ``re2c`` generates an argument in parentheses
- followed by a semicolon after ``YYSETSTATE``. If you need to make ``YYSETSTATE`` an
- arbitrary statement rather than a call, set
- ``re2c:define:YYSETSTATE:naked`` to non-zero and use
- ``re2c:define:YYSETSTATE@cond`` to denote formal parameter inside of
- your ``YYSETSTATE`` body.
-
-``re2c:define:YYSETSTATE@state = "@@";``
- Any occurrence of this text
- inside of ``YYSETSTATE`` will be replaced with the actual argument.
-
-``re2c:define:YYSETSTATE:naked = 0;``
- Controls the argument in parentheses and the
- semicolon after ``YYSETSTATE``. If zero, both argument and the semicolon are
- omitted. If non-zero, both the argument and the semicolon are generated.
-
-``re2c:define:YYLIMIT = "YYLIMIT";``
- Replaces the ``YYLIMIT`` placeholder with the specified identifier.
- needed.
-
-``re2c:define:YYMARKER = "YYMARKER";``
- Replaces the ``YYMARKER`` placeholder with the specified identifier.
-
-``re2c:label:yyFillLabel = "yyFillLabel";``
- Overrides the name of the ``yyFillLabel`` label.
-
-``re2c:label:yyNext = "yyNext";``
- Overrides the name of the ``yyNext`` label.
-
-``re2c:variable:yyaccept = yyaccept;``
- Overrides the name of the ``yyaccept`` variable.
-
-``re2c:variable:yybm = "yybm";``
- Overrides the name of the ``yybm`` variable.
-
-``re2c:variable:yych = "yych";``
- Overrides the name of the ``yych`` variable.
-
-``re2c:variable:yyctable = "yyctable";``
- When both ``-c`` and ``-g`` are active, ``re2c`` will use this variable to generate a static jump table
- for ``YYGETCONDITION``.
-
-``re2c:variable:yystable = "yystable";``
- Deprecated.
-
-``re2c:variable:yytarget = "yytarget";``
- Overrides the name of the ``yytarget`` variable.
-
+++ /dev/null
-Interface
----------
-
-The user must supply interface code either in the form of C/C++ code
-(macros, functions, variables, etc.) or in the form of `configurations`_.
-Which symbols must be defined and which are optional
-depends on the particular use case.
-
-``YYCONDTYPE``
- In ``-c`` mode, you can use ``-t`` to generate a file that
- contains the enumeration used as conditions. Each of the values refers
- to a condition of a rule set.
-
-``YYCTXMARKER``
- l-value of type ``YYCTYPE *``.
- The generated code saves trailing context backtracking information in
- ``YYCTXMARKER``. The user only needs to define this macro if a scanner
- specification uses trailing context in one or more of its regular
- expressions.
-
-``YYCTYPE``
- Type used to hold an input symbol (code unit). Usually
- ``char`` or ``unsigned char`` for ASCII, EBCDIC or UTF-8, or *unsigned short*
- for UTF-16 or UCS-2, or ``unsigned int`` for UTF-32.
-
-``YYCURSOR``
- l-value of type ``YYCTYPE *`` that points to the current input symbol. The generated code advances
- ``YYCURSOR`` as symbols are matched. On entry, ``YYCURSOR`` is assumed to
- point to the first character of the current token. On exit, ``YYCURSOR``
- will point to the first character of the following token.
-
-``YYDEBUG (state, current)``
- This is only needed if the ``-d`` flag was
- specified. It allows easy debugging of the generated parser by calling a
- user defined function for every state. The function should have the
- following signature: ``void YYDEBUG (int state, char current)``. The first
- parameter receives the state or -1 and the second parameter receives the
- input at the current cursor.
-
-``YYFILL (n)``
- The generated code "calls"" ``YYFILL (n)`` when the
- buffer needs (re)filling: at least ``n`` additional characters should be
- provided. ``YYFILL (n)`` should adjust ``YYCURSOR``, ``YYLIMIT``, ``YYMARKER``,
- and ``YYCTXMARKER`` as needed. Note that for typical programming languages
- ``n`` will be the length of the longest keyword plus one. The user can
- place a comment of the form ``/*!max:re2c*/`` to insert a ``YYMAXFILL`` define set to the maximum
- length value.
-
-``YYGETCONDITION ()``
- This define is used to get the condition prior to
- entering the scanner code when using the ``-c`` switch. The value must be
- initialized with a value from the ``YYCONDTYPE`` enumeration type.
-
-``YYGETSTATE ()``
- The user only needs to define this macro if the ``-f``
- flag was specified. In that case, the generated code "calls"
- ``YYGETSTATE ()`` at the very beginning of the scanner in order to obtain
- the saved state. ``YYGETSTATE ()`` must return a signed integer. The value
- must be either -1, indicating that the scanner is entered for the first
- time, or a value previously saved by ``YYSETSTATE (s)``. In the second
- case, the scanner will resume operations right after where the last
- ``YYFILL (n)`` was called.
-
-``YYLIMIT``
- An expression of type ``YYCTYPE *`` that marks the end of the buffer ``YYLIMIT[-1]``
- is the last character in the buffer). The generated code repeatedly
- compares ``YYCURSOR`` to ``YYLIMIT`` to determine when the buffer needs
- (re)filling.
-
-``YYMARKER``
- An l-value of type ``YYCTYPE *``.
- The generated code saves backtracking information in ``YYMARKER``. Some
- simple scanners might not use this.
-
-``YYMAXFILL``
- This will be automatically defined by ``/*!max:re2c*/`` blocks as explained above.
-
-``YYSETCONDITION (c)``
- This define is used to set the condition in
- transition rules. This is only being used when ``-c`` is active and
- transition rules are being used.
-
-``YYSETSTATE (s)``
- The user only needs to define this macro if the ``-f``
- flag was specified. In that case, the generated code "calls"
- ``YYSETSTATE`` just before calling ``YYFILL (n)``. The parameter to
- ``YYSETSTATE`` is a signed integer that uniquely identifies the specific
- instance of ``YYFILL (n)`` that is about to be called. Should the user
- wish to save the state of the scanner and have ``YYFILL (n)`` return to
- the caller, all he has to do is store that unique identifier in a
- variable. Later, when the scanner is called again, it will call
- ``YYGETSTATE ()`` and resume execution right where it left off. The
- generated code will contain both ``YYSETSTATE (s)`` and ``YYGETSTATE`` even
- if ``YYFILL (n)`` is disabled.
-
+++ /dev/null
-Regular expressions
--------------------
-
-``"foo"``
- literal string ``"foo"``. ANSI-C escape sequences can be used.
-
-``'foo'``
- literal string ``"foo"`` (case insensitive for characters [a-zA-Z]).
- ANSI-C escape sequences can be used.
-
-``[xyz]``
- character class; in this case, the regular expression matches ``x``, ``y``, or ``z``.
-
-``[abj-oZ]``
- character class with a range in it; matches ``a``, ``b``, any letter from ``j`` through ``o``, or ``Z``.
-
-``[^class]``
- inverted character class.
-
-``r \ s``
- match any ``r`` which isn't ``s``. ``r`` and ``s`` must be regular expressions
- which can be expressed as character classes.
-
-``r*``
- zero or more occurrences of ``r``.
-
-``r+``
- one or more occurrences of ``r``.
-
-``r?``
- optional ``r``.
-
-``(r)``
- ``r``; parentheses are used to override precedence.
-
-``r s``
- ``r`` followed by ``s`` (concatenation).
-
-``r | s``
- ``r`` or ``s`` (alternative).
-
-``r`` / ``s``
- ``r`` but only if it is followed by ``s``. Note that ``s`` is not
- part of the matched text. This type of regular expression is called
- "trailing context". Trailing context can only be at the end of a rule
- and cannot be part of a named definition.
-
-``r{n}``
- matches ``r`` exactly ``n`` times.
-
-``r{n,}``
- matches ``r`` at least ``n`` times.
-
-``r{n,m}``
- matches ``r`` at least ``n`` times, but not more than ``m`` times.
-
-``.``
- match any character except newline.
-
-``name``
- matches a named definition as specified by ``name`` only if ``-F`` is
- off. If ``-F`` is active then this behaves like it was enclosed in double
- quotes and matches the string "name".
-
-Character classes and string literals may contain octal or hexadecimal
-character definitions and the following set of escape sequences:
-``\a``, ``\b``, ``\f``, ``\n``, ``\r``, ``\t``, ``\v``, ``\\``. An octal character is defined by a backslash
-followed by its three octal digits (e.g., ``\377``).
-Hexadecimal characters from 0 to 0xFF are defined by a backslash, a lower
-case ``x`` and two hexadecimal digits (e.g., ``\x12``). Hexadecimal characters from 0x100 to 0xFFFF are defined by a backslash, a lower case
-``\u``or an upper case ``\X``, and four hexadecimal digits (e.g., ``\u1234``).
-Hexadecimal characters from 0x10000 to 0xFFFFffff are defined by a backslash, an upper case ``\U``,
-and eight hexadecimal digits (e.g., ``\U12345678``).
-
-The only portable "any" rule is the default rule, ``*``.
-
+++ /dev/null
-Rules
------
-
-Each rule consist of a `regular expression`_ accompanied with a block of C/C++ code
-which is to be executed when the associated regular expression is
-matched. You can either start the code with an opening curly brace or
-the sequence ``:=``. If you use an opening curly brace, ``re2c`` will count brace depth
-and stop looking for code automatically. Otherwise, curly braces are not
-allowed and ``re2c`` stops looking for code at the first line that does
-not begin with whitespace. If two or more rules overlap, the first rule
-is preferred.
-
- ``regular-expression { C/C++ code }``
-
- ``regular-expression := C/C++ code``
-
-There is one special rule: the default rule (``*``)
-
- ``* { C/C++ code }``
-
- ``* := C/C++ code``
-
-Note that the default rule (``*``) differs from ``[^]``: the default rule has the lowest priority,
-matches any code unit (either valid or invalid) and always consumes exactly one character.
-``[^]``, on the other hand, matches any valid code point (not the same as a code unit) and can consume multiple
-code units. In fact, when a variable-length encoding is used, ``*``
-is the only possible way to match an invalid input character.
-
-If ``-c`` is active, then each regular expression is preceded by a list
-of comma-separated condition names. Besides the normal naming rules, there
-are two special cases: ``<*>`` (these rules are merged to all conditions)
-and ``<>`` (these rules cannot have an associated regular expression;
-their code is merged to all actions). Non-empty rules may furthermore specify the new
-condition. In that case, ``re2c`` will generate the necessary code to
-change the condition automatically. Rules can use ``:=>`` as a shortcut
-to automatically generate code that not only sets the
-new condition state but also continues execution with the new state. A
-shortcut rule should not be used in a loop where there is code between
-the start of the loop and the ``re2c`` block unless ``re2c:cond:goto``
-is changed to ``continue``. If some code is needed before all rules (though not before simple jumps), you
-can insert it with ``<!>`` pseudo-rules.
-
- ``<condition-list> regular-expression { C/C++ code }``
-
- ``<condition-list> regular-expression := C/C++ code``
-
- ``<condition-list> * { C/C++ code }``
-
- ``<condition-list> * := C/C++ code``
-
- ``<condition-list> regular-expression => condition { C/C++ code }``
-
- ``<condition-list> regular-expression => condition := C/C++ code``
-
- ``<condition-list> * => condition { C/C++ code }``
-
- ``<condition-list> * => condition := C/C++ code``
-
- ``<condition-list> regular-expression :=> condition``
-
-
- ``<*> regular-expression { C/C++ code }``
-
- ``<*> regular-expression := C/C++ code``
-
- ``<*> * { C/C++ code }``
-
- ``<*> * := C/C++ code``
-
- ``<*> regular-expression => condition { C/C++ code }``
-
- ``<*> regular-expression => condition := C/C++ code``
-
- ``<*> * => condition { C/C++ code }``
-
- ``<*> * => condition := C/C++ code``
-
- ``<*> regular-expression :=> condition``
-
-
- ``<> { C/C++ code }``
-
- ``<> := C/C++ code``
-
- ``<> => condition { C/C++ code }``
-
- ``<> => condition := C/C++ code``
-
- ``<> :=> condition``
-
- ``<> :=> condition``
-
-
- ``<! condition-list> { C/C++ code }``
-
- ``<! condition-list> := C/C++ code``
-
- ``<!> { C/C++ code }``
-
- ``<!> := C/C++ code``
-
Code for ``re2c`` consists of a set of `rules`_, `definitions`_ and
`configurations`_.
+Rules
+----------
+
+Each rule consist of a `regular expression`_ accompanied with a block of C/C++ code
+which is to be executed when the associated regular expression is
+matched. You can either start the code with an opening curly brace or
+the sequence ``:=``. If you use an opening curly brace, ``re2c`` will count brace depth
+and stop looking for code automatically. Otherwise, curly braces are not
+allowed and ``re2c`` stops looking for code at the first line that does
+not begin with whitespace. If two or more rules overlap, the first rule
+is preferred.
+
.. include:: rules.rst_
Definitions
``name { regular-expression }``
+Configurations
+--------------
+
.. include:: configurations.rst_
+
+Regular expressions
+-------------------
+
.. include:: regular_expressions.rst_
+
+Interface
+----------
+
+The user must supply interface code either in the form of C/C++ code
+(macros, functions, variables, etc.) or in the form of `configurations`_.
+Which symbols must be defined and which are optional
+depends on the particular use case.
+
.. include:: interface.rst_
+++ /dev/null
-
-``-W``
- Turn on all warnings.
-
-``-Werror``
- Turn warnings into errors. Note that this option alone
- doesn't turn on any warnings; it only affects those warnings that have
- been turned on so far or will be turned on later.
-
-``-W<warning>``
- Turn on a ``warning``.
-
-``-Wno-<warning>``
- Turn off a ``warning``.
-
-``-Werror-<warning>``
- Turn on a ``warning`` and treat it as an error (this implies ``-W<warning>``).
-
-``-Wno-error-<warning>``
- Don't treat this particular ``warning`` as an error. This doesn't turn off
- the warning itself.
-
+++ /dev/null
-``-Wcondition-order``
- Warn if the generated program makes implicit
- assumptions about condition numbering. You should use either the ``-t, --type-header`` option or
- the ``/*!types:re2c*/`` directive to generate a mapping of condition names to numbers and then use
- the autogenerated condition names.
-
-``-Wempty-character-class``
- Warn if a regular expression contains an empty
- character class. Rationally, trying to match an empty
- character class makes no sense: it should always fail. However, for
- backwards compatibility reasons, ``re2c`` allows empty character classes and
- treats them as empty strings. Use the ``--empty-class`` option to change the default
- behavior.
-
-``-Wmatch-empty-string``
- Warn if a regular expression in a rule is
- nullable (matches an empty string). If the DFA runs in a loop and an empty match
- is unintentional (the input position in not advanced manually), the lexer may
- get stuck in an infinite loop.
-
-``-Wswapped-range``
- Warn if the lower bound of a range is greater than its upper
- bound. The default behavior is to silently swap the range bounds.
-
-``-Wundefined-control-flow``
- Warn if some input strings cause undefined
- control flow in the lexer (the faulty patterns are reported). This is the
- most dangerous and most common mistake. It can be easily fixed by adding
- the default rule (``*``) (this rule has the lowest priority, matches any code unit, and consumes
- exactly one code unit).
-
-``-Wunreachable-rules``
- Warn about rules that are shadowed by other rules and will never match.
-
-``-Wuseless-escape``
- Warn if a symbol is escaped when it shouldn't be.
- By default, re2c silently ignores such escapes, but this may as well indicate a
- typo or error in the escape sequence.
projects / re2c / commitdiff