TS7006

Parameter implicitly has an any type

Parameter 'value' implicitly has an 'any' type.

The compiler’s own words. Not translated — this is the string you pasted into a search box.

Strict mode found a function parameter with no annotation and no surrounding context from which to infer one.

Reproduction

function double(value) {
  return value * 2
}

The build asserts this emits exactly this code.

Why the compiler says this

An untyped parameter is an unchecked entrance to the function. With `noImplicitAny`, TypeScript refuses to let callers send anything through that entrance unless the contract says what belongs there.

Fixes

01
```
function double(value: number) {
  return value * 2
}
```
Annotate the concrete input when the operation really requires a number.
02
```
function identity<T>(value: T): T {
  return value
}
```
Use a type parameter when the function preserves whatever type the caller supplies.

Takeaway

Do not replace an implicit `any` with an explicit one by reflex. Describe the real input, or model the relationship with a generic.

Where to go next

Generic parameters #268 Append an argument Try it in the Lab

Errors