Manual page for hashtable-entries(3scm)

hashtable-entries - get the entries in the hashtable as two vectors

LIBRARY

(import (rnrs))                     ;R6RS
(import (rnrs hashtables))          ;R6RS

SYNOPSIS

(hashtable-entries hashtable)

DESCRIPTION

Returns a vector of the keys in hashtable and a vector of the corresponding values.

RETURN VALUES

Returns two values; two vectors of equal length.

EXAMPLES

(let ((h (make-eqv-hashtable)))
  (hashtable-set! h 1 'one)
  (hashtable-set! h 2 'two)
  (hashtable-set! h 3 'three)
  (hashtable-entries h))
    => #(1 2 3)
       #(one two three)
            ; entries may be in different order

APPLICATION USAGE

This procedure is used when iterating over the entries of a hashtable in an indeterminate order or when you need all the associated values from a hashtable.

RATIONALE

If a program needs all entries in a hashtable then this procedure is significantly faster than using hashtable-keys(3scm) together with hashtable-ref(3scm) for each key, because it does not need to use the hash and equal functions.

COMPATIBILITY

This procedure is unique to R6RS. An equivalent procedure can be found in SRFI-125 under the name hash-table-entries.

ERRORS

This procedure can raise exceptions with the following condition types:

&assertion (R6RS): The wrong number of arguments was passed or an argument was outside its domain.

STANDARDS

R6RS

HISTORY

This procedure first appeared in R6RS.

AUTHORS

This page is part of the scheme-manpages project. It includes materials from the RnRS documents. More information can be found at https://github.com/schemedoc/manpages/.

Markup created by unroff 1.0sc, March 04, 2023.