slice
Factor handbook » The language » Collections » Sequence operations » Subsequences and slices

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Vocabulary
sequences

Class description
A virtual sequence which presents a subrange of the elements of an underlying sequence. New instances can be created by calling <slice>. Convenience words are also provided for creating slices where one endpoint is the start or end of the sequence; see Subsequences and slices for a list.

Slices are mutable if the underlying sequence is mutable, and mutating a slice changes the underlying sequence. However, slices cannot be resized after creation.

Definition

USING: math ;

IN: sequences

TUPLE: slice
    { from integer read-only initial: 0 }
    { to integer read-only initial: 0 } { seq read-only } ;

Methods

USING: accessors alien kernel math sequences ;

M: slice >c-ptr
    [ [ from>> ] [ element-size ] bi * ] [ seq>> >c-ptr ] bi
    <displaced-alien> ; inline


USING: accessors alien sequences ;

M: slice element-size seq>> element-size ; inline


USING: kernel sequences ;

M: slice equal? over slice? [ sequence= ] [ 2drop f ] if ;


USING: kernel math sequences ;

M: slice hashcode* [ sequence-hashcode ] recursive-hashcode ;


USING: accessors kernel math sequences ;

M: slice length [ to>> ] [ from>> ] bi - ; inline


USING: accessors kernel math sequences ;

M: slice virtual@ [ from>> + ] [ seq>> ] bi ; inline


USING: io kernel modern.out sequences ;

M: slice write-literal* [ write-whitespace ] [ write ] [ ] tri ;