Run-Time Function Parameter Name Determination
This is a tiny JavaScript function for determining the names of the
parameters of a function under run-time. It can be used as the building
block for Dependency Injection or Named-Parameter implementations.
The underlying problem is that there is no official JavaScript API
to determine the names of the parameters of a function under run-time,
except the ECMAScript 2015 Function.prototype.toString(). This
library determines the names of the function parameters by parsing
the source code of Function.prototype.toString(). Its parsing is not
100%, but is able to handle even complex syntax scenarios.
$ npm install func-paramsconst funcParams = require("func-params")
/* simple example */
funcParams(function (a, b, c, d) {})
// --> [ "a", "b", "c", "d" ]
/* complex example */
funcParams(function (
a /* x,y */ = /* x,y */ `foo\`baz${bar + ",)" + (42 / 7)}bar`,
b = x(42, 7),
c = { foo: { bar: x(42, 7), baz: [ 2 / 3 ] } },
d = 42
) {})
// --> [ "a", "b", "c", "d" ]Copyright (c) 2018-2021 Dr. Ralf S. Engelschall (http://engelschall.com/)
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