dict_size

Abstract

Returns the number of key:value pairs in a dict

Description

A hashtable is a mapping from a key to a value. The dict_ family of opcodes implement a hashtable mapping either strings or integers to strings or floats.

dict_size returns the number of such key:value pairs inside a dict. If the handle passed does not point to a valid dict, dict_size returns -1. It is thus possible to use it to check that the passed handle is valid (similar to dict_query idict "exists", see dict_query)

dict_size can be used together with dict_iter to iterate over the key:value pairs

Syntax

isize dict_size idict
ksize dict_size idict

dict_size executes both at i-time and k-time.

Arguments

ìdict: the handle of the dict, as returned by dict_new

Output

ksize: the number of key:value pairs in the dict

Execution Time

Init
Performance

Examples

<CsoundSynthesizer>
<CsOptions>

--nosound

</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2

instr 1 
  ; create a local dict, mapping strings to numbers
  idict dict_new "sf"

  ; set key a key:value pair
  dict_set idict, "bar", 123

  ksize = dict_size(idict)
  printf "size: %d", 1, ksize

  dict_set idict, "foo", 4
  ksize = dict_size(idict)
  printf "size: %d", 1, ksize

  ; size does not change now
  dict_set idict, "foo", 10
  ksize = dict_size(idict)
  printf "size: %d", 1, ksize

  ; we delete a key, size is reduced
  dict_set idict, "foo"
  ksize = dict_size(idict)
  printf "size: %d", 1, ksize

  turnoff
endin


</CsInstruments>
<CsScore>

i 1 0 1

</CsScore>
</CsoundSynthesizer>

Credits

Eduardo Moguillansky, 2019