Inside a function or macro, I frequently need specific SetOverwrite behavior. However, I prefer to have these subprograms clean up after themselves (not leaving non-return values on the stack, keeping the OutPath the same, not altering global states, etc.) so that I don't have to copy a stream of settings commands every time I want to do something—in order to keep the code more readable.
Is there a way to accomplish this with SetOverwrite? Can I "detect" it, save it, and restore it somehow?
There's no GetOverwrite function that I can see. The SetOverwrite docs refer to the "overwrite flag," though I can't find concrete references to what exactly that is. Is there a way I can get the value of this (or an arbitrary) flag?
You cannot save the current state of the flag in a variable, but SetOverwrite allows you to use lastused as an argument, which restores the value of the flag which was used before the last SetOverwrite. So you cannot save the flag recursively, but you can set it temporary before File and restore it after it:
${If} $something = "whatever"
SetOverwrite on
${Else}
SetOverwrite ifnewer
${EndIf}
File "foo.txt"
SetOverwrite lastused