boolean operation not casting datatype to bool

[half leaf]

The two inspected elements yield different page numbers. The isTitlePage variable is a bool (or so it seems) and yet I cannot use it for an if statement; see error message.

[raw reef]

could you paste your typst code?

[dusk salmon]

dont do that

that will never return true

cuz when u write context code(), code() isnt evaluated immediately, it's delayed until the document is laid out

otherwise it doesnt have access to the context

instead you have to declare all of your code depending on context stuff as dependent on context

[half leaf]

[title page: ]; context counter(page).at(<Abstract>).first(); linebreak()
  [this page: ]; context counter(page).at(here()).first(); linebreak()
  
  let isTitlePage = context counter(page).at(<Abstract>).first() == context counter(page).at(here()).first()
  
  isTitlePage; linebreak()
  
  if isTitlePage {
    [yes]
  } else {
    [no]
  }

[dusk salmon]

in other words you'd write

context {
  let isTitlePage = counter(page)...etc == counter(page)...etc
  // ...
  if isTitlePage [yes] else [no]
}

[half leaf]

okay, I don't really understand what it means to decalare depending on context, or independent of context for that matter. I'll read up on it a bit more

[dusk salmon]

generally code is run before your document is laid out

so your code isnt aware of the amount of pages in the document, amount of headings, its own location in the document, stuff like that

thats what context provides

it does that by creating a document element

similar to a heading, figure, and others you know

but what that element does is: run your code and display what it returns

but at layout time, after code outside it

more info here: https://typst.app/docs/reference/context/

[dusk salmon]

you still need context

just not where it was before

[dusk salmon]

but here

[half leaf]

ahh, I misread that

it works now. Thanks! I'm currently rewriting my department's latex template to typst, it's a great exercise, but the learning curve is kinda steep

[dusk salmon]

np

yea typst is pretty powerful but you gotta get used to its idioms

[half leaf]

for sure. I really need to learn contexts :p

[dusk salmon]

dont worry, it's simpler than it sounds :p

it was much more confusing in the past

there were like 2 different functions (style(styles => ...) and locate(loc => ...)) which used callbacks

meaning you had to manually pass that particular bit of the context around as a parameter

context { } does both under the hood for you

so anything that depends on the context to work (e.g. here() to get the current location) will just receive the context as a parameter "implicitly"

but only when inside a context block

otherwise it will complain

[half leaf]

so is the point of the context block make the piece of code reactive to where it is called rather than where it is declared?

[dusk salmon]

yeah!

[half leaf]

great! I've been wondering all afternoon how to do that 😅 thanks a bunch

[dusk salmon]

no problem

[storm jasper]

Kind of a tangent to the main point of this thread but related to this ^

Can I update old code that used locate to just use a context block instead?

[dusk salmon]

yes

you should actually

[storm jasper]

Ok awesome

[dusk salmon]

there are some things that still need a location though

but for those it makes sense

and then you can use let loc = here()

e.g. if you want to access the value of a counter at a specific location you use .at(loc)

but to get at the current location you dont have to counter("...").at(here()), you can just counter("...").get()