Creates a function that invokes the predicate properties of source with the corresponding property values of a given object, returning true if all predicates return truthy, else false. Part of Lodash Util since 4.0.0 (stable — not deprecated).
Note: Equivalent to _.conformsTo with source partially applied.
Call _.conforms. Start with this line.
_.conforms(source)| Call | What it does |
|---|---|
_.conforms(source) | Primary signature. |
_.conforms(...) | Call the util helper. |
Prefer import conforms from "lodash/conforms" when you want a smaller bundle.
_.conforms(source)| Parameter | Description |
|---|---|
| source | Required. Object of property predicates |
| Return Value | Description |
|---|---|
| * | New spec function (object) => boolean |
b > 1Keep objects whose b property passes a predicate.
var objects = [
{ a: 2, b: 1 },
{ a: 1, b: 2 }
];
_.filter(objects, _.conforms({ b: function (n) { return n > 1; } }));
// → [{ a: 1, b: 2 }]_.conforms({ b: … }) builds a checker for key b.b is 1 → 1 > 1 is false → dropped.b is 2 → passes → kept.[{ a: 1, b: 2 }].Call the returned function on one object.
var isActive = _.conforms({
active: function (v) { return v === true; }
});
console.log(isActive({ id: 1, active: true })); // true
console.log(isActive({ id: 2, active: false })); // falseactive.active: true → predicate truthy → true.active: false → predicate false → false.isActive works in filters or guards.Every listed key must pass — like AND across properties.
var ok = _.conforms({
age: function (n) { return n >= 18; },
score: function (n) { return n >= 70; }
});
console.log(ok({ age: 20, score: 80 })); // true
console.log(ok({ age: 20, score: 50 })); // false
console.log(ok({ age: 16, score: 90 })); // falseage and score must pass.true.false.false.Keys not in source are not checked.
var hasBigB = _.conforms({
b: function (n) { return n > 1; }
});
console.log(hasBigB({ a: 9, b: 2, c: 'x' })); // true
console.log(hasBigB({ b: 0, z: 1 })); // falseb only.a and c are ignored.b: 2 satisfies > 1.b: 0 fails even if z exists.conforms vs matchesPredicates vs exact (partial) value matching.
var obj = { a: 1, b: 2 };
console.log(_.conforms({ b: function (n) { return n > 1; } })(obj));
// → true
console.log(_.matches({ b: 2 })(obj));
// → true
console.log(_.matches({ b: 3 })(obj));
// → falseb → range/type checks.b: 2 matches both styles here._.conforms is a Lodash Util helper since 4.0.0. It runs anywhere Lodash runs — modern browsers (CDN or bundle) and Node.js / Bun / Deno with npm install lodash.
Available in [email protected] full builds and the lodash/conforms modular import. Works in evergreen browsers and current Node LTS when Lodash is installed.
Bottom line: Safe for production once Lodash is loaded. Prefer import conforms from "lodash/conforms" for smaller bundles. Use it to build reusable property-predicate checkers for filter and cond.
Create a function that always returns the same value.
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