dict_query

Abstract

Query different properties of a dict

Description

Properties of a dict which do not need a separate opcode (because they are not used very frequently) are merged togehter in this opcode. Possible properties are:

exists: return 1 if the handle points to a valid dict
size: returns the size of this dict (similar to dict_size)
type: returns an integer identifying the type of this dict
11: number -> number
12: number -> string
21: string -> number
22: string -> string
keys: returns an array with all the keys defined in this dict (the type of the returned array depends on the type of the keys)
values: returns an array with all the values (the type of the returned array depends on the type of the values).

NB: the order in which keys and values are returned represents the corresponding pairs, so keys[i] and values[i] belong to the same pair.

dict_query executes at k-time.

Syntax

kexists   dict_query idict, "exists"
ksize     dict_query idict, "size"
ktype     dict_query idict, "type"
SKeys[]   dict_query idict, "keys"
kKeys[]   dict_query idict, "keys"
kValues[] dict_query idict, "values"
SValues[] dict_query idict, "values"

Arguments

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

Output

NB: the arrays returned from keys and values can have either an S- or a k-type, depending on the type definition of the array

Execution Time

Performance

Examples

<CsoundSynthesizer>
<CsOptions>
--nosound 
</CsOptions>
<CsInstruments>

/*

  Example file for dict_query

  ... dict_query idict, Scmd

  where Scmd can be: 'size', 'type', 'exists', 'keys', 'values'

*/


instr 1
  ; get all the keys as an array
  idict1 dict_new "sf", 0, "keyA", 1, "keyB", 2, "keyC", 3
  ; check that the dict exists
  kexists dict_query idict1, "exists"
  ktype   dict_query idict1, "type"
  printf "dict exists = %d, type = %d \n", 1, kexists, ktype

  SKeys[] dict_query idict1, "keys"
  printarray SKeys

  ; now check a bogus handle
  kexists999 dict_query 999, "exists"
  printf "dict 999 exists = %d \n", 1, kexists999

  ; get the keys from a different dict
  idict2 dict_new "if", 0, 1,100, 10,1000, 2,200
  kKeys[] dict_query idict2, "keys"
  printarray kKeys, 1, "%.0f"
  printf "idict2 has size=%d\n", 1, dict_query(idict2, "size")

  ; get values as an array
  idict3 dict_new "is", 0, 10, "foo", 20, "bar", 30, "baz"
  Svals[] dict_query idict3, "values"
  printarray Svals


  kVals[] dict_query idict2, "values"
  printarray kVals

  ; query the type of the dict
  ktype  dict_query idict2, "type"
  printf "the type of dict %d is %d\n", 1, idict2, ktype  

  turnoff
endin

</CsInstruments>
<CsScore>
i 1 0 0.1
</CsScore>
</CsoundSynthesizer>

Credits

Eduardo Moguillansky, 2019