-- This file checks the usage checking on channels

PROC read(CHAN OF INT c)
  INT x:
  c ? x
:

PROC write(CHAN OF INT c)
  c ! 0
:

PROC both(CHAN OF INT c)
  INT x:
  SEQ
    c ? x
    c ! x
:

PROC both.2(CHAN OF INT c, CHAN OF INT d)
  PAR
    read(c)
    write(d)
:

PROC m()
  CHAN OF INT c, d, e:
%%
:

%PASS Safe direct use of each
  PAR
    c ! 1
    d ! 2
    e ! 3
%PASS Safe direct use of each with overlap
  INT x, y, z:
  PAR
    c ! 1
    c ? x
    d ! 2
    d ? y
    e ! 3
    e ? z
%FAIL Unsafe direct use of each with overlap
  INT x, y, z:
  PAR
    c ! 1
    c ? x
    d ! 2
    d ? x
    e ! 3
    e ? x
    c ! 4
%PASS Safe direct/indirect use of each with overlap
  INT x, y, z:
  PAR
    write(c)
    c ? x
    read(d)
    d ! 4
    both.2(e,e)
%FAIL Unsafe direct/indirect use of each with overlap
  INT x, y, z:
  PAR
    write(c)
    c ? x
    read(d)
    d ! 4
    both.2(e,e)
    e ! 5
%FAIL Unsafe direct/indirect use of each with overlap 2
  INT x, y, z:
  PAR
    write(c)
    c ? x
    read(d)
    d ? y
    both.2(e,e)
%