lexer.js Documentation
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Methods
lexer.lex(str, spec)-
Given a string and a lexer specification, return matched
Lexeme objects (see below) as an array. The expected format
of the lexer specification is described below.
Specification Object Properties
states-
An object with user-defined keys whose values are arrays of
pattern objects as described below. These pattern objects are
attempted to be used to match the input string to the lexer in
the order specified by the array.
start_state-
A string matching one of the keys of
states.
Pattern Object Properties
regex-
A regular expression to be matched against the part of the
lexer input string that hasn't yet been matched.
next_state (optional)-
A string corresponding to the key of a state in the
specification object described above. If the regex matches,
transition to this state.
type (optional)-
The type of lexeme, to be returned as part of the Lexeme
object (see below).
Lexeme Object Properties
type-
The type of lexeme, as specified in the Pattern object (see
above).
val-
The value of the matched regex pattern as specified in the
Pattern object (see above).
line-
The 0-indexed line of the source file on which the lexeme
appears.