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Programming-Idioms

  • Ruby
  • Python
  • C#
  • Perl

Idiom #123 Assert condition

Verify that predicate isConsistent returns true, otherwise report assertion violation.
Explain if the assertion is executed even in production environment or not.

use PerlX::Assert;
assert { is_consistent };
raise unless isConsistent

There's no assert method in Ruby standard library
assert isConsistent

raises AssertionError Exception.

Running Python with option -O or with PYTHONOPTIMZE
environment variable suppresses all asserts.
using System.Diagnostics;
var result = isConsistent();
Trace.Assert(result);

Trace assertion (included in Release builds)
using System.Diagnostics;
var result = isConsistent();
Debug.Assert(result);

Debug assertion (removed from Release builds).
It is considered unsafe to call a function directly in a debug assertion because any side-effects in the function won't affect Release builds.
#include <assert.h>
assert(isConsistent());

If NDEBUG is defined, the assert macro becomes void. Therefore, such expressions must not have side effects.
New implementation...
< > ⌨
programming-idioms.org 
assert { is_consistent };
raise unless isConsistent
assert isConsistent
var result = isConsistent();
Trace.Assert(result);
var result = isConsistent();
Debug.Assert(result);
assert(isConsistent());
(assert (isConsistent))
(assert (true? (isConsistent)))
assert(isConsistent());
assert(isConsistent);
assert(isConsistent);
if (.not. isconsistent) stop "Inconsistent state"
if !isConsistent() {
	panic("State consistency violated")
}
assert isConsistent()
let x' = assert isConsistent x
console.assert(_isConsistent);

assert isConsistent() : "State consistency violated";
(assert (isConsistent))
assert(isConsistent() , "Assertion violation") 
assert(_isConsistent);
{$ASSERTIONS ON}
Assert(isConsistent,'isConsistent assertion failed.');
assert!(is_consistent);