2reduce ( ... seq1 seq2 identity quot: ( ... prev elt1 elt2 -- ... next ) -- ... result )
Factor handbook » The language » Collections » Sequence operations » Sequence combinators » Pair-wise sequence combinators

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Vocabulary
sequences

Inputs

seq1	a sequence
seq2	a sequence
identity	an object
quot	a quotation with stack effect ( ... prev elt1 elt2 -- ... next )

Outputs

result

the final result

Word description
Combines successive pairs of elements from the two sequences using a ternary operation. The first input value at each iteration except the first one is the result of the previous iteration. The first input value at the first iteration is identity.

See also
vdot

Definition

USING: kernel ;

IN: sequences

: 2reduce
    ( ... seq1 seq2 identity quot: ( ... prev elt1 elt2 -- ... next ) -- ... result )
    -rotd 2each ; inline