assert

assert() Function

• Introduced in version 1.3b49

Halts execution and prints a custom error message if a condition is false(0). Note that the error message will be displayed in chat even if the command itself is in a [H: ] block.

Usage

<source lang="mtmacro" line> assert(condition, message) </syntaxhighlight> <source lang="mtmacro" line> assert(condition, message, prefix) </syntaxhighlight> Parameters

• condition - The test condition that must evaluate to true(1) for the macro to continue.
• message - The custom error message that is presented if the macro is halted due to the false(0) condition.
• prefix - Determines if the error message should have the message prefix "Macro defined error: ". Defaults to true(1), set to false(0) if you do not wish your custom error message to have the message prefix.

Examples

Checks to see if a player is a GM, and if they are not halts execution of the macro and displays output.

<source lang="mtmacro" line> [h: assert(isGM(),"This macro is for GM use only.",0)] </syntaxhighlight> Chat output (if player is not GM): This macro is for GM use only.

Halts execution of the macro if var is a number. This is useful for making sure the variables you work with are the variable type you expect. <source lang="mtmacro" line> [h: assert(! isNumber(var), "The variable is a number.",1)] </syntaxhighlight> Chat output (if var is a number): Macro defined error: The variable is a number.

Bear in mind, isNumber(var) returns true(1) when var is a number, but assert continues when condition is true(1). Using ! isNumber(var) inverts the boolean value.

Usage Notes

When aborting a macro called from another macro (for example, a library token), all macros are aborted, not just the one executing.

Since 1.5.0 you can change that behaviour by using macro.catchAssert.

See Also

isGM()

isNumber() abort()

macro.catchAssert

Version Changes

• 1.3b51 - Added prefix parameter option.
• 1.5.0 - catch an assert with macro.catchAssert