Cannot index into static array or object

[chetbox]

Hi! Thanks for this great library!

I just came across something I had assumed would work but it doesn't seem to.

["zero", "one", "two", "three"][1]

(Playground link)

Gives this error:

Error: Token [ (openBracket) unexpected in expression: ["zero", "one", "two", "three"][

Similarly,

{foo: 1}['foo']

(Playground link)

Gives this error:

Error: Token [ (openBracket) unexpected in expression: {foo: 1}[

It's possible to index into and array or an object if it's part of the Jexl context but seemingly not statically like this.

[chetbox]

Some context for this is I'm trying to write an expression that give me a random string from a static list.

["One","Two","Three"][(random() * 3) | floor]

Am I going about this the wrong way?

[TomFrost]

Oh wow -- I see why that's happening. Definitely a bug!

Until this is fixed, you could throw this into a transform function:

jexl.addTransform('random', (ary) => {
  const idx = Math.floor(Math.random() * ary.length)
  return ary[idx]
})

Now your expression becomes ['one', 'two', 'three']|random

[chetbox]

Until this is fixed, you could throw this into a transform function:

jexl.addTransform('random', (ary) => {
  const idx = Math.floor(Math.random() * ary.length)
  return ary[idx]
})

This will do for now. Thanks!

[ablsc]

To avoid raising duplicate issues it looks as if what chetbox has raised means static JSON as parameters to functions isn't currently possible with jexl right now.

The following expression

"aFunction(aVariable, { \"aProperty\": 1 })"

raises the error

Error: Token "aProperty" (literal) unexpected in expression: aFunction(aVariable, { "aProperty"

By changing the expression to the following and parsing the string in aFunction as JSON does work

"aFunction(aVariable, \"{ \\\"aProperty\\\": 1 }\")"

I wondered if transforms might help but parsing bombs out just the same.