assert()

[iseahound]

assert(true) ; Do Nothing
assert(false) ; Exit

[swagfag]

Code: Select all

assert(bool) {
    if (bool = false)
        exitapp
}

[Chunjee]

perhaps related: https://www.npmjs.com/package/assert.ahk

[guest3456]

a few of us have also contributed to this unit testing framework over the years, i use it regularly, and lexikos used it to test the new Object.ahk changes in v2:

https://github.com/Uberi/Yunit

[Delta Pythagorean]

I don't quite understand what Hound is asking for.

[SpeedMaster]

I use similar functions myself exitapp() msgbox()..., these small functions are very useful to create ternary and one-liners. I'm still wondering why they're not built in...
here an example:

Code: Select all

#singleinstance force

myvar:=true

(myvar=1) && msgbox("myvar is true") && beep() && assert(false)

msgbox, you will only see this message if myvar is "false" or if assert is set to "true".

msgbox(message:="") {
msgbox, % message
return 1
}

beep() {
soundbeep
return 1
}

assert(bool:=false) {
    if (bool = false)
        exitapp
return 1
}

What would be really interesting is to have a stop() or return() function. I mean something that would stop the script instead of exiting it. Any idea ?

Not working example

Code: Select all

#singleinstance force

myvar:=true

(myvar=1) && return()

msgbox, how to prevent the script to get here ? (with a one-liner and without closing the script) 

q::msgbox, hello world

esc::exitapp

return() {
return
}

[guest3456]

What would be really interesting is to have a stop() or return() function. I mean something that would stop the script instead of exiting it. Any idea ?

Pause?
https://www.autohotkey.com/docs/commands/Pause.htm

but for what purpose?

[HotKeyIt]

Probably Exit?

Code: Select all

return(){
Exit
}

[SpeedMaster]

but for what purpose?

to make one-liners

Probably Exit ?

Code: Select all

return(){
Exit
}

Great! That seems to solve the problem.
I'll add it to my personal library.

here is a test script (set myvar to true and then to false and see what happens)

Code: Select all

#singleinstance force

myvar:=true

(myvar=1) ? msgbox("myvar is true") && return() : beep() && beep()

msgbox, myvar is false
return

q::msgbox, hello world


esc::exitapp

beep() {
soundbeep
return 1
}

msgbox(message:="") {
msgbox, % message
return 1
}

return() {
Exit
}

[norths1]

i think the OP wants an alternative for assert() as in Lua.
This function handles errors and won't let your program crash if an error occurs.

sorry if i got it wrong

[lexikos]

Generally, assert() or ASSERT() will not merely exit the program. It is a debugging tool which can have a range of effects, but usually includes showing an error dialog indicating that an assertion failed. The dialog may have more or less information, depending on the language and whether debugging is enabled. For instance, the dialog may have:

• The expression that was evaluated by assert() and found to be false, such as "x == y" in ASSERT(x == y);.
• The location of the assert() in the source code.
• A stack trace.
• A button to attach a debugger.

I believe it could be done in script with Exception() and some clever parsing of script code, with some minor limitations.

If a debugger is attached, a failed assertion may act as a breakpoint, switching focus to the debugger/IDE. Either way is a lot more useful than merely exiting the program.

If you merely want to exit the thread or program in a one-liner, in v2 you can simply call Exit() or ExitApp(). You can obviously do the same in v1 after defining either function, but I would suggest to avoid calling the function "return".

@norths1

Spoiler

The assert function checks whether its first argument is not false and simply returns that argument; if the argument is false (that is, false or nil), assert raises an error.
Source: Programming in Lua : 8.3

If you need to handle errors in Lua, you should use the pcall function (protected call) to encapsulate your code.
Source: Programming in Lua : 8.4

[iseahound]

@lexikos It might be worth looking at integrating it into the control flow instead. On this website for a derivative language of Python,

https://www.pyret.org/docs/latest/A_Tour_of_Pyret.html

They use where blocks and check blocks to hold a series of unit tests. The where block seems to be attached to a function definition, and the check block is freestanding. I can’t tell which approach is better, assert or where, but the idea of a fee-standing check block in combination with a #directive to turn unit testing on or off seems to be very powerful.

https://www.pyret.org/ has interesting comparisons of different languages.