how to run debug mode, save some codes

[FbiCirno]

i need a switch that can switch 'debug code' on build.

such as:
@debug function printdebug( string txt)
print(txt)

if i ban debug in opt
'printdebug' will not build

[Frotty]

just use an if with a global constant variable and it will be optimized away.

constant IS_DEBUG = true
function printDebug(string txt)
    if IS_DEBUG
        ...

You could also use the isProductionBuild variable.