dict-clear
Syntax: (dict-clear d)
Library: (scm core)
Description: Removes all key-value associations from the dictionary d, leaving it empty.
Example:
(let ((d (make-dict)))
(dict-put d "key" 1)
(dict-clear d)
(dict-size d)) => 0
(scm dict)
Dictionary / associative map operations
Overview
(scm dict) is a simple mutable dictionary (associative map) with a small, readable API. For richer hash-table functionality (custom comparators, folding, set operations) see (srfi 69) and (srfi 125); (scm dict) is handy when you just want a quick mutable key/value store.
Common uses
(import (scm dict))
(define d (make-dict))
(dict-put d "a" 1)
(dict-put d "b" 2)
(dict-get d "a") ;; => 1
(dict-size d) ;; => 2
(dict-contains d "b") ;; => #t
(dict-keys d) ;; => ("a" "b")
(dict-values d) ;; => (1 2)dict-entries returns the key/value pairs, and dict-clear empties the dictionary in place.
9 bindings
dict-contains
Syntax: (dict-contains d key)
Library: (scm core)
Description: Returns #t if the dictionary d contains an entry for key (a string or symbol), otherwise returns #f.
Example:
(let ((d (make-dict)))
(dict-put d "x" 42)
(dict-contains d "x")) => #t
dict-entries
Syntax: (dict-entries d)
Library: (scm core)
Description: Returns a list of (key . value) pairs for all entries in the dictionary d.
Example:
(let ((d (make-dict)))
(dict-put d "a" 1)
(dict-entries d)) => (("a" . 1))
dict-get
Syntax: (dict-get d key) (dict-get d key default)
Library: (scm core)
Description: Returns the value associated with key in the dictionary d. If the key is not found and a default is given, returns it; otherwise raises an error.
Example:
(let ((d (make-dict)))
(dict-put d "x" 42)
(dict-get d "x")) => 42
dict-keys
Syntax: (dict-keys d)
Library: (scm core)
Description: Returns a list of all keys (as strings) in the dictionary d.
Example:
(let ((d (make-dict)))
(dict-put d "a" 1)
(dict-put d "b" 2)
(dict-keys d)) => ("a" "b")
dict-put
Syntax: (dict-put d key value)
Library: (scm core)
Description: Associates key (a string or symbol) with value in the dictionary d. If the key already exists, the old value is replaced.
Example:
(let ((d (make-dict)))
(dict-put d "x" 42)
(dict-get d "x")) => 42
dict-size
Syntax: (dict-size d)
Library: (scm core)
Description: Returns the number of key-value entries in the dictionary d.
Example:
(let ((d (make-dict)))
(dict-put d "a" 1)
(dict-size d)) => 1
dict-values
Syntax: (dict-values d)
Library: (scm core)
Description: Returns a list of all values in the dictionary d.
Example:
(let ((d (make-dict)))
(dict-put d "a" 1)
(dict-values d)) => (1)
make-dict
Syntax: (make-dict)
Library: (scm core)
Description: Returns a new empty mutable dictionary (hash map) with string or symbol keys.
Example:
(let ((d (make-dict)))
(dict-put d "key" 42)
(dict-get d "key")) => 42