epsilon-loop ( state table nfa question -- )

Vocabulary

regexp.dfa

Inputs

state	an object
table	an object
nfa	an object
question	an object

Outputs

None

Definition

USING: accessors arrays assocs kernel regexp.ast regexp.classes
sequences ;

IN: regexp.dfa

:: epsilon-loop ( state table nfa question -- )
    state table at :> old-value old-value question 2array
    <or-class> :> new-question new-question old-value = [
        new-question state table set-at
        state nfa transitions>> at
        [ tagged-epsilon? ] filter-keys [| trans to |
            to [
                table nfa trans tag>> new-question 2array
                <and-class> epsilon-loop
            ] each
        ] assoc-each
    ] unless ;