respect-validation/docs/rules/Lazy.md

Lazy

• Lazy(callable(mixed $input): Rule $ruleCreator)

Validates the input using a rule that is created from a callback.

This rule is particularly useful when creating rules that rely on the input. A good example is validating whether a confirmation field matches the password field when processing data from a form.

v::key('confirmation', v::equals($_POST['password'] ?? null))->isValid($_POST);

The issue with the code is that it’s hard to reuse because you’re relying upon the input itself ($_POST). That means you can create a chain of rules and use it everywhere.

The lazy() rule makes this job much simpler and more elegantly:

v::lazy(static fn($input) => v::key('confirmation', v::equals($input['password'] ?? null)))->isValid($_POST);

The code above is similar to the first example, but the biggest difference is that the creation of the rule doesn't rely on the input itself ($_POST), but it will use any input that’s given to the rule

Templates

Template placeholders

Placeholder	Description
name	The validated input or the custom validator name (if specified).

Categorization

• Callables
• Nesting

Changelog

Version	Description
3.0.0	Created from KeyValue

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See also:

• Call
• CallableType
• Circuit