compact ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )

Vocabulary

sequences.extras

Inputs

seq	a sequence
quot	a quotation with stack effect ( ... elt -- ... ? )
elt	an object

Outputs

seq'	a sequence

Word description

Generate a new sequence where all runs of elements for which the predicate returns true are replaced by a single instance of elt. Runs at the beginning or end of the sequence for which the predicate returns true are removed.

See also

collapse

Examples

Collapse multiple spaces in a string down to a single space

USING: kernel prettyprint sequences.extras ; " Hello, crazy world " [ CHAR: \s = ] " " compact .
"Hello, crazy world"

Definition

USING: kernel sequences splitting ;

IN: sequences.extras

: compact
    ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )
    [ split-when harvest ] dip join ; inline