assert

Check that condition is true.

Syntax

• assert(x)
• r = assert(x)
• [r, msg] = assert(x)
• assert(x, err_msg)
• r = assert(x, err_msg)
• [r, msg] = assert(x, err_msg)

Input argument

• x - a logical value
• err_msg - a string, the error message to be printed in case of failure (optional).

Output argument

• res - a logical value
• msg - a string value, the error message. If x == true, then msg == ''. If x == false, then msg contains the error message.

Description

Raises an error if x is false. Raises an error if x is not a logical.

Example

assert(4 == 3, _('error for comparaison.'))

See also

assert_istrue, assert_isfalse.

History

Author

Allan CORNET