class Lexer
package hxparse
Lexer matches a sequence of characters against a set of rule patterns.
An instance of Lexer is created once for each input and maintains state
for that input. Tokens can then be obtained by calling the token method,
passing an instance of Ruleset.
Rule sets can be created manually, or by calling the static buildRuleset
method.
Constructor
new (input:ByteData, ?sourceName:String)
Creates a new Lexer for input.
If sourceName is provided, it is used in error messages to denote
the position of an error.
If input is null, the result is unspecified.
Variables
read onlycurrent:String
The String that was matched by the most recent invocation of the
token method.
Methods
token<T> (ruleset:Ruleset<T>):T
Returns the next token according to ruleset.
This method starts with ruleset.state and reads characters from this
input until no further state transitions are possible. It always returns
the longest match.
If a character is read which has no transition defined, an
UnexpectedChar exception is thrown.
If the input is in the end of file state upon method invocation,
ruleset.eofFunction is called with this Lexer as argument. If
ruleset defines no eofFunction field, a haxe.io.Eof exception
is thrown.
If ruleset is null, the result is unspecified.
Static methods
staticbuildRuleset<Token> (rules:Array<{rule:String, func:Lexer ‑> Token}>, ?name:String):Ruleset<Token>
Builds a Ruleset from the given rules Array.
For each element of rules, its rule String is parsed into a
Pattern using LexEngine.parse.
If rules is null, the result is unspecified.