breakpoint-if ( word quot: ( ... -- ... ? ) -- )
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Vocabulary
tools.walker

Inputs

word	a word
quot	a quotation with stack effect ( ... -- ... ? )

Outputs
None

Word description
Annotates a word definition to enter the single stepper if the quotation yields true. The quotation has access to the datastack as it exists just before word is called. Use reset to clear.

Examples
Break if the input to sq is 3:

USE: tools.walker \ sq [ dup 3 = ] breakpoint-if

Definition

USING: kernel sequences tools.annotations tools.continuations ;

IN: tools.walker

: breakpoint-if ( word quot: ( ... -- ... ? ) -- )
    [ [ [ break ] when ] ] curry [ dip 3append ] curry annotate
    ;