How to use `eval` to recover declared variable?

Questions
1

Hello everyone,

For a personal project i have automated imports of pages into main.typ using a json file with the following structure :

{
    "reglement": [],
    "officiel": [
        "Braban\u00e7onne",
        "WoltjeKreet",
        "Gaudeamus",
        "IoVivat",
        "marche_etudiants",
        "LiedVanGeenTaal",
        "WoltjeClubLied"
    ],
    "leekes": [],
    "groupe_folklorique": [],
    "andere": [],
    "index": [],
    "others": [
        "fulltext",
        "repetition"
    ]
}

Basically, the keys in the following json file represent section of the the future text and the array represent variables to include.

I retrieve the content of the json in a dict and i iterate over each “section” and “variable”. After that i use eval() to call and use my variables :

// in main.typ

#import "imports.typ" : * // for importing variables

// normal call of my variable previously defined
#sacre_page
#WoltjeClubLied
#CridesPres
#Gaudeamus
#Brabançonne  // Variable brabançonne here
#marche_etudiants
#IoVivat
#LiedVanGeenTaal

// using json, dictionnary and eval
#for key in dict.keys() {
  for songname in dict.at(key){
    "#" + str(songname) + linebreak() // used to debug -> correct names
    eval("#" + str(songname), mode : "markup") // unknown variable Brabançonne 
  }
}

I suppose it could be due to the scope of the evaluated code that is not the same as the code located on top. Unfortunately i don’t really know how to correctly define it.
Another supposition is to evaluate the code including the #import "imports.typ" : *

For more insight you can check the project here : Typst and main.typ should be the most useful file to check.
( :warning: It is quite big and partially automated via python script so not everything make sense. )
Thank you in advance for your help

2

The import hypothesis was correct so i implemented the following workaround :

#let dict = json("songs.json")

#for key in dict.keys() {
  
  for songname in dict.at(key){
    eval(str("import \"imports.typ\" : *\n")+str(songname), mode: "code")
  }
}

I still think there’s a better way to do the same since for each song of each new page we make the same import.
For the moment it will be marked as solution

3

The eval function has a scope parameter. Let’s say I have

// imports.typ
#let foo = "hello"

// main.typ
#import "imports.typ": *

#foo  // hello

then using the scope parameter I could also write

#import "imports.typ": *

#eval("foo", mode: "code", scope: (foo: foo))

This is not useful yet, since you’d have to write all the variable names. However you can use the dictionary constructor to convert a module (imports.typ) into a dictionary, and pass that as the scope:

#import "imports.typ" as imports

#eval("foo", mode: "code", scope: dictionary(imports))

(as an aside, I used mode: "code" to avoid having to add the # to the variable)

You may notice that you’re not doing a lot with eval, and you have a dictionary already. So you can further simplify this to

#import "imports.typ" as imports

#dictionary(imports).at("foo")
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