tzfile>transitions ( tzfile -- transitions )

Vocabulary

tzinfo.private

Inputs

tzfile

an object

Outputs

transitions

an object

Definition

USING: accessors assocs calendar combinators kernel sequences ;

IN: tzinfo.private

:: tzfile>transitions ( tzfile -- transitions )
    tzfile abbrevs>> tznames :> abbrevs tzfile is-std>>
    :> is-std tzfile is-gmt>> :> is-gmt tzfile types>> [
        [
            {
                [ tt_gmtoff>> seconds ]
                [ tt_isdst>> 1 = ]
                [ tt_abbrind>> abbrevs at ]
            } cleave
        ] dip
        [ is-std ?nth dup [ 1 = ] when ]
        [ is-gmt ?nth dup [ 1 = ] when ] bi <local-time>
    ] map-index
    :> local-times tzfile transition-times>> tzfile
    local-times>> [
        [ dup unix-time>timestamp ] [ local-times nth ] bi*
        <transition>
    ] 2map ;