@template tag doesn't work in @typedefs

/**
 * @template {T}
 * @typedef {(x: T, y: T) => number} SetComparer
 */

Expected: x and y have type T
Actual: x any y have type any, and T is associated with whatever declaration follows the JSDoc comment...

For example the following

/**
 * @template {T}
 * @typedef {(x: T, y: T) => number} SetComparer
 */
class C {
}

makes C generic on T.

Sean Larkin (@TheLarkInn)

Tagging my self for watching this Sean Larkin (@TheLarkInn)

#23511 fixes your second example, which I believe is the one observed in webpack. It does not fix this example:

/**
 * @template {V}
 * @typedef {(v: V) => V} Identity
 * @type Identity
 */
var id = t => t;
var x = id(1)

id gets the type (v: V) => V not <V>(v: V) => V, and therefore doesn't infer V=number and instantiate x as number.

Never mind, this works.

/**
 * @typedef {<V>(v: V) => V} Identity
 * @type Identity
 */
var id = t => t;
var x = id(1)

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@template tag doesn't work in @typedefs #23385

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@template tag doesn't work in @typedefs #23385

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TheLarkInn commented on Apr 12, 2018

sandersn commented on Apr 18, 2018

sandersn commented on Apr 18, 2018

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