By the end of this tutorial, you’ll use Lodash’s _.overEvery() to build reusable AND-style predicates that must all pass on the same arguments.
_.overEvery([predicates])
All must be truthy.
Like _.over fan-out.
Not result array.
matches objects.
All vs any.
_.overEvery()?_.overEvery(predicates) is the boolean sibling of _.over(). Instead of returning every predicate result in an array, it returns true only when every predicate is truthy for the same argument list—logical AND across independent checks.
Build once: const isValid = _.overEvery([ruleA, ruleB]). Call many times: isValid(value) → true or false. Each predicate receives the same arguments you pass to the combinator.
Use it for validation rules, authorization gates, and filter predicates where several conditions must hold together.
Pass an array of predicate functions or shorthands:
_.overEvery([predicates = [_.identity]])predicates — array of functions; defaults to [_.identity].true or false._.matches; [path, value] arrays use _.matchesProperty.Array.every).import overEvery from "lodash/overEvery";
const isTruthyFinite = overEvery([Boolean, Number.isFinite]);
isTruthyFinite("1");
// true
isTruthyFinite(null);
// false| Task | Code pattern | Notes |
|---|---|---|
| Two number rules | _.overEvery([isEven, gt10])(n) | AND combo |
| Official demo | _.overEvery([Boolean, isFinite]) | Truthy + finite |
| Filter array | _.filter(items, combo) | Reuse predicate |
| matches shorthand | _.overEvery([{ active: true }]) | Partial match |
| vs overSome | _.overSome([...]) | Any truthy |
| vs over | _.over([...]) | Array of results |
FunctionPredicate
ANDAll truthy
BooleanPass / fail
UtilPredicate
Arguments to _.overEvery() and the combinator it returns:
predicates OptionalArray of predicate functions or iteratee shorthands. Defaults to [_.identity].
_.overEvery([fn1, fn2])returned fn CombinatorForwards received arguments to each predicate; returns true only if all pass.
combo(value)shorthand object matchesPartial object—predicate passes when the argument object matches (like _.matches).
{ role: "admin" }shorthand array matchesProperty[path, value] pair—predicate checks one property equals value.
["status", "active"]For collection-wide “every element passes one predicate” use _.every(collection, predicate)—overEvery builds the predicate first.
Practical _.overEvery() patterns with copy-ready code, sample output, and interactive Try It Yourself labs.
Combine two numeric predicates and the official Lodash demo.
Classic AND combo—both rules must pass on the same number.
const isEven = (n) => n % 2 === 0;
const isGreaterThanTen = (n) => n > 10;
const isEvenAndGt10 = _.overEvery([isEven, isGreaterThanTen]);
console.log(isEvenAndGt10(12));
console.log(isEvenAndGt10(7));
// true
// falseBoth predicates receive 12 or 7. 7 fails isEven, so the combinator returns false immediately.
Boolean + isFiniteLodash docs pattern for truthy, finite values.
const isTruthyFinite = _.overEvery([Boolean, Number.isFinite]);
console.log(isTruthyFinite("1"));
console.log(isTruthyFinite(null));
console.log(isTruthyFinite(NaN));
// true
// false
// falseBoolean("1") and Number.isFinite("1") are both truthy/true. null and NaN fail at least one check.
Validation, authorization, and filtering.
Required non-empty string that looks like an email.
const isRequired = (val) => val != null && val !== "";
const isEmail = (val) => /\S+@\S+\.\S+/.test(val);
const validateEmail = _.overEvery([isRequired, isEmail]);
console.log(validateEmail("ada@example.com"));
console.log(validateEmail(""));
// true
// falseCompose small single-purpose validators, then reuse validateEmail on blur, submit, or in unit tests.
Combine function predicates with a partial object match.
const isAdmin = (user) => user.role === "admin";
const canManage = _.overEvery([
isAdmin,
{ status: "verified" },
]);
console.log(canManage({ role: "admin", status: "verified" }));
console.log(canManage({ role: "user", status: "verified" }));
// true
// falseThe object { status: "verified" } becomes a _.matches predicate on the same user argument.
Each product is passed to every rule—correct use with _.filter.
const products = [
{ name: "Laptop", price: 1200, brand: "Dell" },
{ name: "Phone", price: 800, brand: "Samsung" },
{ name: "Tablet", price: 400, brand: "Apple" },
];
const isExpensive = (p) => p.price > 1000;
const isDell = (p) => p.brand === "Dell";
const expensiveDell = _.overEvery([isExpensive, isDell]);
console.log(_.filter(products, expensiveDell));
// [{ name: "Laptop", price: 1200, brand: "Dell" }]_.filter calls expensiveDell(product) per item. Both predicates receive that same product object.
overEvery vs over vs overSome on the same rules.
Same two predicates—three different combinators.
const rules = [(n) => n > 0, (n) => n % 2 === 0];
const n = 4;
console.log(_.over(rules)(n));
console.log(_.overEvery(rules)(n));
console.log(_.overSome(rules)(n));
// [true, true] — individual results
// true — all passed
// true — at least one passed (both here)
console.log(_.overEvery(rules)(3));
// false — odd fails second ruleNeed every result? over. Need all pass? overEvery. Need any pass? overSome (next tutorial).
_.overEvery() WorksShorthands become functions; default is [_.identity].
The predicate waits for values at test time.
Same args forwarded; stop early when one returns falsy.
true only when every predicate passed.
overEvery is AND logic—use overSome for OR._.matches partial matching—not deep equality._.every(array, fn), not overEvery on the array itself unless intentional._.overEvery() packages AND-style rules into one reusable predicate. Build it once, pass it to filters or guards, and keep each rule small and testable.
Pair it with matches shorthands for object checks, and reach for overSome when any single passing rule is enough.
_.filter, _.find, or guards_.over_.every(collection) without reading the API_.overEvery()Use these points when all rules must pass together.
All truthy.
LogicLike over.
MechanicsPass/fail.
Outputmatches.
IterateeOR next.
CompareThe Lodash docs use _.overEvery([Boolean, isFinite]) because '1' is truthy and finite, while null and NaN fail—one combinator, three clear test cases.
Combine numeric rules, run the official Boolean/isFinite demo, and filter products.
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