GeneralFunctions\encodeProperty()

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higher-order returns Closure pure

(string, (T → U)) → ((T, Record) → Record)

At a glance — Building block for recordEncoder. Each encoder step knows which key it writes and how to compute its value from the source data.

Creates a Closure for use inside a recordEncoder() — pairs a property key with a function that produces its value from the input data.

/**
  * @param string $key
  * @param callable(mixed):mixed $value
  * @return Closure(mixed):mixed
  */
GeneralFunctions\encodeProperty(string $key, callable $value): Closure

What it does (and what it doesn’t)

encodeProperty doesn’t touch any data by itself. It bundles a key with a way to compute its value — nothing more. The bundle is useful only inside recordEncoder, which collects many of these bundles and runs them over a source record to build an output record.

Think of it as declaring one row of a transformation table:

 output key       |  computed from source via
 -----------------+---------------------------------------
 'id'             |  getProperty('id')
 'displayName'    |  fn($u) => ucfirst($u['first']) . ' ' . ucfirst($u['last'])
 'isAdmin'        |  propertyEquals('role', 'admin')
 'country'        |  pluckProperty('profile', 'country')

Each row is one encodeProperty call. The value callable can be anything — getProperty, pluckProperty, a closure, a composed pipeline from compose, a conditional from ifElse. All that matters is that it takes the source record and returns the value for that output field.

Why this indirection is useful

If you just wanted $output['displayName'] = strtoupper($source['name']) you could write exactly that. The separation pays off once you have several fields:

Each encoder is a first-class callable — test it, log it, reuse it across encoders.
The transformation is data, not control flow. You can filter or reorder your encoders based on configuration, permission rules, or anything else you like before recordEncoder runs them.
Swapping array output for object output means changing the seed record passed to recordEncoder — the encodeProperty calls don’t change.

Full walked example

See Transforming complex objects for the whole pattern — building a view model from a list of API records with encodeProperty for every output field plus recordEncoder to assemble them.

Examples

Partial Application

This can be used to create a simple closure which can be used as a regular function.

// One encoder step: the 'displayName' output field is computed from the source by upper-casing its 'name'.
$encodeName = GeneralFunctions\encodeProperty(
  'displayName',
  fn($src) => strtoupper($src['name'])
);

// On its own encodeProperty does nothing — it records the intent. The work happens inside recordEncoder.
$toViewModel = GeneralFunctions\recordEncoder([])($encodeName);

print_r($toViewModel(['name' => 'Ada']));  // ['displayName' => 'ADA']

GeneralFunctions\encodeProperty()

What it does (and what it doesn’t)

Why this indirection is useful

Full walked example

Examples

Partial Application

Details

General Functions

Releated Record encoder Functions