#! perl -slw
use strict;
use threads;

async{ print 'from thread' }->detach;

require OpenGL;
OpenGL->import( ':all' );
...

##</code><code>##

c:\test>GLex7.2.pl
Bareword "GL_FRONT" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 15.
Bareword "GL_AMBIENT" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 15.
Bareword "GL_FRONT" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 16.
Bareword "GL_SPECULAR" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 16.
Bareword "GL_FRONT" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 17.
Bareword "GL_SHININESS" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 17.
Bareword "GL_LIGHTING" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 19.
Bareword "GL_LIGHT0" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 20.
Bareword "GL_LEQUAL" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 21.
Bareword "GL_DEPTH_TEST" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 22.
Bareword "GL_FALSE" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 25.
Bareword "GLUT_DOUBLE" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 84.
Bareword "GLUT_RGBA" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 84.
Bareword "GLUT_DEPTH" not allowed while "strict subs" in use at c:\test\GLex7.2.pl line 84.
Execution of c:\test\GLex7.2.pl aborted due to compilation errors.

##</code><code>##

c:\test>GLex7.2.pl
from thread
Argument "GLUT_VOWWLE" isn't numeric in subroutine entry at c:\test\GLex7.2.pl line 84.
Argument "GL_FRONT" isn't numeric in subroutine entry at c:\test\GLex7.2.pl line 15.
Argument "GL_AMBIENT" isn't numeric in subroutine entry at c:\test\GLex7.2.pl line 15.
Unknown material parameter at c:\test\GLex7.2.pl line 15.