refvalid

Abstract

Queries if a reference is valid

Description

ref and deref implement a mechanism to pass a reference to any object, allowing to share a variable across instruments, with opcodes, etc. A reference is a proxy to an axisting variable / array. A reference is reference counted and deallocates itself when it falls out of scope without being referenced by any object. Since a reference is just an integer, refvalid can be used to check if the given reference index corresponds to a valid reference

Syntax

iout refvalid iref
kout refvalid kref

Arguments

iref / kout: an integer identifying the reference handle, as passed via ref

Output

ìout / kout: 1 if the reference is valid, 0 otherwise

Execution Time

Init
Performance

Examples

<CsoundSynthesizer>
<CsOptions>
-m0
-d
</CsOptions>

<CsInstruments>
sr     = 44100
ksmps  = 64
nchnls = 2
0dbfs  = 1

instr 1
  kfreq linseg 0, p3, 1
  schedule 2, 0, p3, ref(kfreq)
endin

instr 2
  if refvalid(p4) == 1 then
    kfreq = deref(p4)
  else
    kfreq = 1000
  endif
  asig vco2 0.2, kfreq
  schedule 3, 0, p3, ref(asig)
endin

instr 3
  if refvalid(p4) == 1 then
    ain deref p4
  else
    ain = 0
  endif
  aout lpf18 ain, 2000, 0.9, 0.2
  outs aout, aout
endin

Credits

Eduardo Moguillansky, 2019