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  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
/lib/ -> lexer.php (source)

PHP lexer code snarfed from the CVS tree for the lamplib project at http://sourceforge.net/projects/lamplib This project is administered by Markus Baker, Harry Fuecks and Matt Mitchell, and the project  code is in the public domain. Thanks, guys!

Copyright: Markus Baker, Harry Fuecks and Matt Mitchell
License: Public Domain {@link http://sourceforge.net/projects/lamplib}
File Size: 443 lines (16 kb)
Included or required:0 times
Referenced: 0 times
Includes or requires: 0 files

Defines 6 classes

ParallelRegex:: (2 methods):
  __construct()
  ParallelRegex()

name:: (16 methods):
  addPattern()
  match()
  _getCompoundedRegex()
  _getPerlMatchingFlags()
  getCurrent()
  enter()
  leave()
  addPattern()
  addEntryPattern()
  addExitPattern()
  addSpecialPattern()
  mapHandler()
  parse()
  _dispatchTokens()
  _invokeParser()
  _reduce()

StateStack:: (2 methods):
  __construct()
  StateStack()

name:: (16 methods):
  addPattern()
  match()
  _getCompoundedRegex()
  _getPerlMatchingFlags()
  getCurrent()
  enter()
  leave()
  addPattern()
  addEntryPattern()
  addExitPattern()
  addSpecialPattern()
  mapHandler()
  parse()
  _dispatchTokens()
  _invokeParser()
  _reduce()

Lexer:: (2 methods):
  __construct()
  Lexer()

name:: (16 methods):
  addPattern()
  match()
  _getCompoundedRegex()
  _getPerlMatchingFlags()
  getCurrent()
  enter()
  leave()
  addPattern()
  addEntryPattern()
  addExitPattern()
  addSpecialPattern()
  mapHandler()
  parse()
  _dispatchTokens()
  _invokeParser()
  _reduce()


Class: ParallelRegex  - X-Ref

Compounded regular expression. Any of
the contained patterns could match and
when one does it's label is returned.

__construct($case)   X-Ref
Constructor. Starts with no patterns.

param: bool $case    True for case sensitive, false

ParallelRegex($case)   X-Ref
Old syntax of class constructor. Deprecated in PHP7.


Class: name  - X-Ref

addPattern($pattern, $label = true)   X-Ref
Adds a pattern with an optional label.

param: string $pattern      Perl style regex, but ( and )
param: string $label        Label of regex to be returned

match($subject, &$match)   X-Ref
Attempts to match all patterns at once against
a string.

param: string $subject      String to match against.
param: string $match        First matched portion of
return: bool             True on success.

_getCompoundedRegex()   X-Ref
Compounds the patterns into a single
regular expression separated with the
"or" operator. Caches the regex.
Will automatically escape (, ) and / tokens.


_getPerlMatchingFlags()   X-Ref
Accessor for perl regex mode flags to use.

return: string       Flags as string.

getCurrent()   X-Ref
Accessor for current state.

return: string State as string.

enter($state)   X-Ref
Adds a state to the stack and sets it
to be the current state.

param: string $state        New state.

leave()   X-Ref
Leaves the current state and reverts
to the previous one.

return: bool     False if we drop off

addPattern($pattern, $mode = "accept")   X-Ref
Adds a token search pattern for a particular
parsing mode. The pattern does not change the
current mode.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this

addEntryPattern($pattern, $mode, $new_mode)   X-Ref
Adds a pattern that will enter a new parsing
mode. Useful for entering parenthesis, strings,
tags, etc.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $new_mode     Change parsing to this new

addExitPattern($pattern, $mode)   X-Ref
Adds a pattern that will exit the current mode
and re-enter the previous one.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Mode to leave.

addSpecialPattern($pattern, $mode, $special)   X-Ref
Adds a pattern that has a special mode.
Acts as an entry and exit pattern in one go.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $special      Use this mode for this one token.

mapHandler($mode, $handler)   X-Ref
Adds a mapping from a mode to another handler.

param: string $mode        Mode to be remapped.
param: string $handler     New target handler.

parse($raw)   X-Ref
Splits the page text into tokens. Will fail
if the handlers report an error or if no
content is consumed. If successful then each
unparsed and parsed token invokes a call to the
held listener.

param: string $raw        Raw HTML text.
return: bool           True on success, else false.

_dispatchTokens($unmatched, $matched, $mode = false)   X-Ref
Sends the matched token and any leading unmatched
text to the parser changing the lexer to a new
mode if one is listed.

param: string $unmatched    Unmatched leading portion.
param: string $matched      Actual token match.
param: string $mode         Mode after match. The "_exit"
return: bool              False if there was any error

_invokeParser($content, $is_match)   X-Ref
Calls the parser method named after the current
mode. Empty content will be ignored.

param: string $content        Text parsed.
param: string $is_match       Token is recognised rather

_reduce(&$raw)   X-Ref
Tries to match a chunk of text and if successful
removes the recognised chunk and any leading
unparsed data. Empty strings will not be matched.

param: string $raw  The subject to parse. This is the
return: bool|array  Three item list of unparsed

Class: StateStack  - X-Ref

States for a stack machine.

__construct($start)   X-Ref
Constructor. Starts in named state.

param: string $start        Starting state name.

StateStack($start)   X-Ref
Old syntax of class constructor. Deprecated in PHP7.


Class: name  - X-Ref

addPattern($pattern, $label = true)   X-Ref
Adds a pattern with an optional label.

param: string $pattern      Perl style regex, but ( and )
param: string $label        Label of regex to be returned

match($subject, &$match)   X-Ref
Attempts to match all patterns at once against
a string.

param: string $subject      String to match against.
param: string $match        First matched portion of
return: bool             True on success.

_getCompoundedRegex()   X-Ref
Compounds the patterns into a single
regular expression separated with the
"or" operator. Caches the regex.
Will automatically escape (, ) and / tokens.


_getPerlMatchingFlags()   X-Ref
Accessor for perl regex mode flags to use.

return: string       Flags as string.

getCurrent()   X-Ref
Accessor for current state.

return: string State as string.

enter($state)   X-Ref
Adds a state to the stack and sets it
to be the current state.

param: string $state        New state.

leave()   X-Ref
Leaves the current state and reverts
to the previous one.

return: bool     False if we drop off

addPattern($pattern, $mode = "accept")   X-Ref
Adds a token search pattern for a particular
parsing mode. The pattern does not change the
current mode.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this

addEntryPattern($pattern, $mode, $new_mode)   X-Ref
Adds a pattern that will enter a new parsing
mode. Useful for entering parenthesis, strings,
tags, etc.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $new_mode     Change parsing to this new

addExitPattern($pattern, $mode)   X-Ref
Adds a pattern that will exit the current mode
and re-enter the previous one.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Mode to leave.

addSpecialPattern($pattern, $mode, $special)   X-Ref
Adds a pattern that has a special mode.
Acts as an entry and exit pattern in one go.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $special      Use this mode for this one token.

mapHandler($mode, $handler)   X-Ref
Adds a mapping from a mode to another handler.

param: string $mode        Mode to be remapped.
param: string $handler     New target handler.

parse($raw)   X-Ref
Splits the page text into tokens. Will fail
if the handlers report an error or if no
content is consumed. If successful then each
unparsed and parsed token invokes a call to the
held listener.

param: string $raw        Raw HTML text.
return: bool           True on success, else false.

_dispatchTokens($unmatched, $matched, $mode = false)   X-Ref
Sends the matched token and any leading unmatched
text to the parser changing the lexer to a new
mode if one is listed.

param: string $unmatched    Unmatched leading portion.
param: string $matched      Actual token match.
param: string $mode         Mode after match. The "_exit"
return: bool              False if there was any error

_invokeParser($content, $is_match)   X-Ref
Calls the parser method named after the current
mode. Empty content will be ignored.

param: string $content        Text parsed.
param: string $is_match       Token is recognised rather

_reduce(&$raw)   X-Ref
Tries to match a chunk of text and if successful
removes the recognised chunk and any leading
unparsed data. Empty strings will not be matched.

param: string $raw  The subject to parse. This is the
return: bool|array  Three item list of unparsed

Class: Lexer  - X-Ref

Accepts text and breaks it into tokens.
Some optimisation to make the sure the
content is only scanned by the PHP regex
parser once. Lexer modes must not start
with leading underscores.

__construct(&$parser, $start = "accept", $case = false)   X-Ref
Sets up the lexer in case insensitive matching
by default.

param: object $parser     Handling strategy by
param: string $start      Starting handler.
param: bool $case       True for case sensitive.

Lexer(&$parser, $start = "accept", $case = false)   X-Ref
Old syntax of class constructor. Deprecated in PHP7.


Class: name  - X-Ref

addPattern($pattern, $label = true)   X-Ref
Adds a pattern with an optional label.

param: string $pattern      Perl style regex, but ( and )
param: string $label        Label of regex to be returned

match($subject, &$match)   X-Ref
Attempts to match all patterns at once against
a string.

param: string $subject      String to match against.
param: string $match        First matched portion of
return: bool             True on success.

_getCompoundedRegex()   X-Ref
Compounds the patterns into a single
regular expression separated with the
"or" operator. Caches the regex.
Will automatically escape (, ) and / tokens.


_getPerlMatchingFlags()   X-Ref
Accessor for perl regex mode flags to use.

return: string       Flags as string.

getCurrent()   X-Ref
Accessor for current state.

return: string State as string.

enter($state)   X-Ref
Adds a state to the stack and sets it
to be the current state.

param: string $state        New state.

leave()   X-Ref
Leaves the current state and reverts
to the previous one.

return: bool     False if we drop off

addPattern($pattern, $mode = "accept")   X-Ref
Adds a token search pattern for a particular
parsing mode. The pattern does not change the
current mode.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this

addEntryPattern($pattern, $mode, $new_mode)   X-Ref
Adds a pattern that will enter a new parsing
mode. Useful for entering parenthesis, strings,
tags, etc.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $new_mode     Change parsing to this new

addExitPattern($pattern, $mode)   X-Ref
Adds a pattern that will exit the current mode
and re-enter the previous one.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Mode to leave.

addSpecialPattern($pattern, $mode, $special)   X-Ref
Adds a pattern that has a special mode.
Acts as an entry and exit pattern in one go.

param: string $pattern      Perl style regex, but ( and )
param: string $mode         Should only apply this
param: string $special      Use this mode for this one token.

mapHandler($mode, $handler)   X-Ref
Adds a mapping from a mode to another handler.

param: string $mode        Mode to be remapped.
param: string $handler     New target handler.

parse($raw)   X-Ref
Splits the page text into tokens. Will fail
if the handlers report an error or if no
content is consumed. If successful then each
unparsed and parsed token invokes a call to the
held listener.

param: string $raw        Raw HTML text.
return: bool           True on success, else false.

_dispatchTokens($unmatched, $matched, $mode = false)   X-Ref
Sends the matched token and any leading unmatched
text to the parser changing the lexer to a new
mode if one is listed.

param: string $unmatched    Unmatched leading portion.
param: string $matched      Actual token match.
param: string $mode         Mode after match. The "_exit"
return: bool              False if there was any error

_invokeParser($content, $is_match)   X-Ref
Calls the parser method named after the current
mode. Empty content will be ignored.

param: string $content        Text parsed.
param: string $is_match       Token is recognised rather

_reduce(&$raw)   X-Ref
Tries to match a chunk of text and if successful
removes the recognised chunk and any leading
unparsed data. Empty strings will not be matched.

param: string $raw  The subject to parse. This is the
return: bool|array  Three item list of unparsed