Command: unless

Syntax

unless (<condition>)
    <command_block>

Description

Execute a command or block of commands on the failure of a condition.

Parameters

• <condition>
  A conditional phrase yielding a boolean value.

• <command_block>
  One command or a block of commands to be executed if <condition> is false.

Switches

None

Notes

Any non-zero numeric or point, or any non-null string is considered true when evaluating <condition>.

This command may be tied to an else statement which will be executed if <condition> is true.

Examples

Execute one command.

unless ( x = 5 ) !Wrong

Execute a command block.

unless ( x = 5 ) {
    numeric y = 20
    !Have set Y to 20
}

See Also