Class RecordCore

The core Object functions

Since

v1.0.0

Index

Methods

assert assertNot buildValueErr entries is isNot keys omit onKey onKeyEqual onKeyNotEqual pick result values

Methods

`Static`assert

assert<T = undefined>(value: T): asserts value is IsGuard<T, AnyRecord>
Asserts that the given value is an Record.
Type Parameters
- T = undefined
Parameters
- value: T
  The value to check.
Returns asserts value is IsGuard<T, AnyRecord>
Throws
If the value is not an object.

Since
v1.0.0
- Defined in src/lib/RecordCore.mts:51

`Static`assertNot

assertNot<T>(value: T): asserts value is IsNotGuard<T, AnyRecord>
Asserts that the given value is not an Record.
Type Parameters
- T
Parameters
- value: T
  The value to check.
Returns asserts value is IsNotGuard<T, AnyRecord>
Throws
If the value is not an object.

Since
v1.1.0
- Defined in src/lib/RecordCore.mts:64

`Static`buildValueErr

buildValueErr(value: unknown, typeName: "Record", isNot?: boolean): TypeError
Builds value error.
Parameters
- value: unknown
  The invalid value.
- typeName: "Record"
  The type name.
- OptionalisNot: boolean = false
  Whether the error should be for !${typeName}.
Returns TypeError
The created error.

Since
v1.1.2
- Defined in src/lib/RecordCore.mts:296

`Static`entries

entries<R extends object>(value: R): ObjectMappedArrayTuples<R>

Type-safe Object.entries() with overload for NonEmptyArray

Type Parameters

R extends object
The object shape

Parameters

value: R
The object shape to get the values from

Returns ObjectMappedArrayTuples<R>

Array of tuples with key and value

Example

const result1: NonEmptyReadonlyArray<['key', 'value']> = RecordCore.entries({key: 'value'} as const);
const result2: Array<['key', string]> = RecordCore.entries({key: 'value'});
const result3: Array<[string, string]> = RecordCore.entries<Record<string, string>>({key: 'value'});
const result4: [] = RecordCore.entries({});

Since

v1.0.0

`Static`is

is<T = unknown>(value: T): value is IsGuard<T, AnyRecord>
Checks if the given value is an Record.
Type Parameters
- T = unknown
Parameters
- value: T
  The value to check.
Returns value is IsGuard<T, AnyRecord>
True if the value is an object; otherwise, false.

Since
v1.0.0
- Defined in src/lib/RecordCore.mts:31

`Static`isNot

isNot<T = unknown>(value: T): value is IsNotGuard<T, AnyRecord>
Checks if the given value is not an Record.
Type Parameters
- T = unknown
Parameters
- value: T
  The value to check.
Returns value is IsNotGuard<T, AnyRecord>
True if the value is not an object; otherwise, false.

Since
v1.0.0
- Defined in src/lib/RecordCore.mts:41

`Static`keys

keys<R extends object>(value: R): ObjectMappedArray<R, keyof R>
Type-safe Object.keys() with overload for NonEmptyArray
Type Parameters
- R extends object
  The object shape
Parameters
- value: R
  The object shape to get the values from
Returns ObjectMappedArray<R, keyof R>
Array of object keys
Example
```
const result1: NonEmptyReadonlyArray<'key'> = RecordCore.keys({key: 'value'} as const);
const result2: Array<'key'> = RecordCore.keys({key: 'value'});
const result3: Array<string> = RecordCore.keys<Record<string, string>>({key: 'value'});
const result4: [] = RecordCore.keys({});
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:83

`Static`omit

omit<K extends PropertyKey, T extends Partial<Record<K, unknown>>>(
keys: Iterable<K>,
data: T,
): Omit<T, K>
Omit function to omit keys from an object or use as map function to omit keys from an array
Type Parameters
- K extends PropertyKey
  Omit keys
- T extends Partial<Record<K, unknown>>
  Object type
Parameters
- keys: Iterable<K>
  to omit
- data: T
  to omit from (optional)
Returns Omit<T, K>
omitted object or map function
Example
```
type Data = {demo: string, value: number|null};
const data: Data = {demo: 'hello', value: null};
const output: Omit<Data, 'value'> = RecordCore.omit(['value'], data);
const dataArray: Data[] = [{demo: 'hello', value: null}];
const output: Omit<Data, 'demo'>[] = dataArray.map(RecordCore.omit(['demo']));
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:133
omit<K extends PropertyKey>(
keys: Iterable<K>,
): <T extends Partial<Record<K, unknown>>>(value: T) => Omit<T, K>
Type Parameters
- K extends PropertyKey
Parameters
- keys: Iterable<K>
Returns <T extends Partial<Record<K, unknown>>>(value: T) => Omit<T, K>
Deprecated
Use RecordMapper.omit for omit mapping.
- Defined in src/lib/RecordCore.mts:137

`Static`onKey

onKey<
    T extends any[]
    | Record<PropertyKey, any>,
    K extends string | number | symbol,
>(
    key: K,
): (target: T) => T[K]
Creates a function that selects a specific property value from an object.

Useful for use with arrays map function when extracting a single property from each object.
Type Parameters
- T extends any[] | Record<PropertyKey, any>
  Object target from which the property will be selected
- K extends string | number | symbol
  Property name in target that will be selected
Parameters
- key: K
  The property name to select
Returns (target: T) => T[K]
select value by key from the target
Deprecated
Use RecordMapper.prop instead
Example
```
const user1: User = {id: 1, name: 'Alice', role: 'admin', active: true};
const getName = ObjCore.onKey('name');
const output: string = getName(user1);
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:205
onKey<K extends PropertyKey>(
key: K,
): <T extends Record<K, any>>(target: T) => T[K]
Type Parameters
- K extends PropertyKey
Parameters
- key: K
Returns <T extends Record<K, any>>(target: T) => T[K]
Deprecated
Use RecordMapper.prop instead
- Defined in src/lib/RecordCore.mts:209

`Static`onKeyEqual

onKeyEqual<
    T extends Record<PropertyKey, any>,
    K extends string | number | symbol,
>(
    key: K,
    value: T[K],
): (obj: T) => boolean
Creates a predicate function that checks whether a given object's property equals the specified value.

Supports both strictly typed object structures and looser records with optional properties.

Useful for filtering arrays of objects based on property values.
Type Parameters
- T extends Record<PropertyKey, any>
  The object type with known keys (strict overload).
- K extends string | number | symbol
  The key of the property to compare.
Parameters
- key: K
  The property name to compare.
- value: T[K]
  The value to match against.
Returns (obj: T) => boolean
A predicate for use with arrays of type T.
Deprecated
use RecordPredicate.propEq instead.
Example
```
// Strict object structure
const isAdmin = RecordCore.onKeyEqual<User, 'role'>('role', 'admin');
const admins = users.filter(isAdmin);
```
Example
```
// Loosely typed object
const isPublished = RecordCore.onKeyEqual('status', 'published');
const publishedPosts = posts.filter(isPublished);
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:242
onKeyEqual<V, K extends PropertyKey>(
key: K,
value: V,
): (obj: Partial<Record<K, V>>) => boolean
Type Parameters
- V
- K extends PropertyKey
Parameters
- key: K
- value: V
Returns (obj: Partial<Record<K, V>>) => boolean
Deprecated
use RecordPredicate.propEq instead
- Defined in src/lib/RecordCore.mts:246

`Static`onKeyNotEqual

onKeyNotEqual<
    T extends Record<PropertyKey, any>,
    K extends string | number | symbol,
>(
    key: K,
    value: T[K],
): (obj: T) => boolean
Creates a predicate function that checks whether a given object's property does not equal the specified value.

Supports both strictly typed object structures and looser records with optional properties.

Useful for filtering arrays of objects where you want to exclude items with a certain property value.
Type Parameters
- T extends Record<PropertyKey, any>
  The object type with known keys (strict overload).
- K extends string | number | symbol
  The key of the property to compare.
Parameters
- key: K
  The property name to compare.
- value: T[K]
  The value to check against.
Returns (obj: T) => boolean
A predicate function returning true when obj[key] !== value.
Deprecated
use RecordPredicate.propNotEq instead.
Example
```
// Strict object structure
const isNotAdmin = RecordCore.onKeyNotEqual<User, 'role'>('role', 'admin');
const nonAdmins = users.filter(isNotAdmin);
```
Example
```
// Loosely typed object
const isNotPublished = RecordCore.onKeyNotEqual('status', 'published');
const draftsOrArchived = posts.filter(isNotPublished);
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:279
onKeyNotEqual<V, K extends PropertyKey>(
key: K,
value: V,
): (obj: Partial<Record<K, V>>) => boolean
Type Parameters
- V
- K extends PropertyKey
Parameters
- key: K
- value: V
Returns (obj: Partial<Record<K, V>>) => boolean
Deprecated
use RecordPredicate.propNotEq instead
- Defined in src/lib/RecordCore.mts:283

`Static`pick

pick<K extends PropertyKey, T extends Partial<Record<K, unknown>>>(
keys: Iterable<K>,
value: T,
): Pick<T, K>
Pick function to pick keys from an object or use as map function to pick keys from an array
Type Parameters
- K extends PropertyKey
  Pick keys
- T extends Partial<Record<K, unknown>>
  Object type
Parameters
- keys: Iterable<K>
  keys to pick
- value: T
  to pick from (optional)
Returns Pick<T, K>
picked object or map function
Example
```
type Data = {demo: string, value: number|null};
const data: Data = {demo: 'hello', value: null};
const output: Pick<Data, 'value'> = RecordCore.pick(['value'], data);
const dataArray: Data[] = [{demo: 'hello', value: null}];
const output: Pick<Data, 'demo'>[] = dataArray.map(RecordCore.pick(['demo']));
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:169
pick<K extends PropertyKey>(
keys: Iterable<K>,
): <T extends Partial<Record<K, unknown>>>(value: T) => Pick<T, K>
Type Parameters
- K extends PropertyKey
Parameters
- keys: Iterable<K>
Returns <T extends Partial<Record<K, unknown>>>(value: T) => Pick<T, K>
Deprecated
Use RecordMapper.pick for pick mapping.
- Defined in src/lib/RecordCore.mts:173

`Static`result

result<T = unknown>(value: T): CoreResult<IsGuard<T, AnyRecord>, TypeError>
Creates a CoreResult object which contains the result of the validation check.
Type Parameters
- T = unknown
  The type of the value to check.
Parameters
- value: T
  The value to check.
Returns CoreResult<IsGuard<T, AnyRecord>, TypeError>
Core Result object.

Since
v1.1.0
- Defined in src/lib/RecordCore.mts:19

`Static`values

values<R extends object>(value: R): ObjectMappedArray<R, R[keyof R]>
Type-safe Object.values() with overload for NonEmptyArray
Type Parameters
- R extends object
  The object shape
Parameters
- value: R
  The object shape to get the values from
Returns ObjectMappedArray<R, R[keyof R]>
Array of object values
Example
```
const result1: NonEmptyReadonlyArray<'value'> = RecordCore.values({key: 'value'} as const);
const result2: Array<string> = RecordCore.values({key: 'value'});
const result3: [] = RecordCore.values({});
```
Since
v1.0.0
- Defined in src/lib/RecordCore.mts:98

Class RecordCore

Since

Index

Methods

Methods

Staticassert

Type Parameters

Parameters

Returns asserts value is IsGuard<T, AnyRecord>

Throws

Since

StaticassertNot

Type Parameters

Parameters

Returns asserts value is IsNotGuard<T, AnyRecord>

Throws

Since

StaticbuildValueErr

Parameters

Returns TypeError

Since

Staticentries

Type Parameters

Parameters

Returns ObjectMappedArrayTuples<R>

Example

Since

Staticis

Type Parameters

Parameters

Returns value is IsGuard<T, AnyRecord>

Since

StaticisNot

Type Parameters

Parameters

Returns value is IsNotGuard<T, AnyRecord>

Since

Statickeys

Type Parameters

Parameters

Returns ObjectMappedArray<R, keyof R>

Example

Since

Staticomit

Type Parameters

Parameters

Returns Omit<T, K>

Example

Since

Type Parameters

Parameters

Returns <T extends Partial<Record<K, unknown>>>(value: T) => Omit<T, K>

Deprecated

StaticonKey

Type Parameters

Parameters

Returns (target: T) => T[K]

Deprecated

Example

Since

Type Parameters

Parameters

Returns <T extends Record<K, any>>(target: T) => T[K]

Deprecated

StaticonKeyEqual

Type Parameters

Parameters

Returns (obj: T) => boolean

Deprecated

Example

Example

Since

Type Parameters

Parameters

Returns (obj: Partial<Record<K, V>>) => boolean

Deprecated

StaticonKeyNotEqual

Type Parameters

Parameters

Returns (obj: T) => boolean

`Static`assert

`Static`assertNot

`Static`buildValueErr

`Static`entries

`Static`is

`Static`isNot

`Static`keys

`Static`omit

`Static`onKey

`Static`onKeyEqual

`Static`onKeyNotEqual

`Static`pick

`Static`result

`Static`values