attempt-all ( ... seq quot: ( ... elt -- ... obj ) -- ... obj )
Factor handbook » The language » Continuations

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Vocabulary
continuations

Inputs

seq	a sequence
quot	a quotation

Outputs

obj

an object

Word description
Applies the quotation to elements in a sequence and returns the value from the first quotation that does not throw an error. If all quotations throw an error, returns the last error thrown.

Examples
The first two numbers throw, the last one doesn't:

USING: prettyprint continuations kernel math ; { 1 3 6 } [ dup odd? [ "Odd" throw ] when ] attempt-all .
6

All quotations throw, the last exception is rethrown:

USING: prettyprint continuations kernel math ; [ { 1 3 5 } [ dup odd? [ throw ] when ] attempt-all ] [ ] recover .
5

Definition

USING: kernel make sequences ;

IN: continuations

: attempt-all
    ( ... seq quot: ( ... elt -- ... obj ) -- ... obj )
    over empty?
    [ attempt-all-error ] [
        [ [ , f ] compose [ [ , drop t ] recover ] curry all? ]
        { } make last swap [ rethrow ] when
    ] if ; inline