Wolfram/Parser | Paclet Repository

Wolfram`Parser`

ParserCombinator

ParserCombinator [type,args,opts]
	is the single computable wrapper every parser in the library is represented as. The head is opaque to user code: build a ParserCombinator by calling one of the Parse* constructors ( ParseLiteral , ParseSequence , ParseChoice , …), never by hand.

Details and Options

▪

type

is a

Symbol

naming the combinator shape (

Literal

Character

Sequence

Choice

Many

Some

Optional

Between

Lookahead

NotFollowedBy

Try

Action

Capture

Recursive

, …).

▪

args

are the combinator's children: other

ParserCombinator

instances, terminal data (a string for

Literal

, a character class for

Character

), or a function (for

Action

▪

opts

is an

Association

of compile-time / runtime options. After

ParserCompile

the options carry a

"Code"CompiledCodeFunction[...]

entry; absence of

"Code"

is what makes the parser uncompiled (no extra

"Compiled"

flag is needed).

▪

ParserCombinator

is callable as a function via a

SubValues

rule:

pc[input]

is equivalent to

Parse[pc,input]

. If

"Code"

is present in

opts

, the compiled function is invoked; otherwise the interpretive path runs.

▪

ParserCombinator

carries

UpValues

for the WL operators that overload to combinator composition:

WL syntax	UpValue	Combinator
p1\|p2	Alternatives	ParseChoice
p1~~p2	StringExpression	ParseSequence
p..	Repeated	ParseSome
p...	RepeatedNull	ParseMany
Optional [p]	Optional	ParseOptional