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If variable is not equal...
Hello. I'm having problems with showing hook if variable is NOT equal to something. The code I'm using is
(if: $a is not "")[ Variable `$a` is not empty, instead it's $a!
[[Hooray!]] ]
Comments
//edit: Doesn't work. Either some bug or doesn't work for string variables.
I've put at very end of passage $a for debug purposes and it doesn't update. I'm changing the variable using (click:) hooks, e.g (click ?paragraph)[(set: $a to "asdf")] and it doesn't update it.
1. You should assign a value to your variables before you compare their value using the (if:) macros
2. The (click:) macro in your second example is missing the colon after the word 'click', it should be as follows: 3. The (click:) macro is meant to be used with a "Named hook". I'm not sure if you are doing that but your 2nd example did not include one, but it would look something like the following: 4. Variables set within (click:) macros only change value after the related hook is clicked on, as demostrated in the following:
Well, code was anonymized as I don't want to spoil my story. There are, of course, named hooks there. But the issue is that when I update variable within the click macro, all instances of $a in story should change and ifs should be recalculated. Example:
If you want the text to change try the following: A similar thing happens with (if:) macros, the expression is evaluated as the output is being generated. It is not re-evaluated each time the variable changes, and this is the same way Twine 1 story formats work.
Note that uninitialized Twine variables evaluate to 0, not "", so if you haven't ever set $weapon, you'll get "I am wielding my trusty 0!"
If you want to check whether a variable has been initialized, you can use something like: or: (I don't know which one would be considered "conventional" in Twine, but the difference is stylistic, not functional.)
Regarding the question of updating ?msg, I've been wondering if there's some way of redisplaying a hook without changing its text. I think right now the best way to deal with this is re-set the text each time the user clicks something, but I'm not sure what the most readable/efficient way of doing this is (there are several ways that work, I'm just not sure which one is 'best').
The current version of Harlowe defaults all unassigned variables the value of zero, who's to say this won't be changed for some technical reason in the future.
(unless $var:)[(set: $var to "$var's initial value")]
Obviously, that's relying on Harlowe's defaulting unassigned variables to something that evaluates to false. Unfortunately, any alternative (e.g. using an equivalent of a #ifndef preprocessor directive) also relies on that property.
I don't know what an alternate best practice would be that allows random access debugging (it strikes me as a bad idea to leave out the (unless) because that's just asking to forget to remove the initialization script from the place you're debugging). I was pondering this earlier today, but I didn't come up with anything.
Using a variation of your idea you can do something similar with a bit of work using Harlow.
1. Create a StoryInit passage and use it to setup the default values of your story's variables. Add to the end of this passage a variable named $initialized and give it the value of true. The passage would something like the following:
(note: using open and close curly braces to suppress displaying of blank lines.) 2. Add the following line of code to the top of any passage (including your main passage)) you want to debug.
I'm leaning toward testing (unless: $initialized) in the StoryInit passage, because that is a centralized location to change if for some reason that is no longer the case (there would have to be some other way to make sure the code only got run once).
Sorry for the thread hijack Darkhog
neq" operator in Twine 2 is "is not". You should, er, use that instead of!==etc.