@param-closure-this

The @param-closure-this tag documents what $this refers to inside a Closure parameter. A @param on that same parameter already describes the closure's own signature — the arguments it receives and what it returns — but says nothing about the object it will be bound to when the closure is eventually invoked through Closure::bindTo(), Closure::call(), or an equivalent internal rebinding. Without this tag, code inside the closure that reads $this has no documented type to check against.

"@param-closure-this" <Type> <Variable> [ <Description> ]

Parsing a @param-closure-this tag produces a TypedVariableTag instance exposing:

$type — the documented TypeNode that $this is bound to.
$variable — the closure parameter's name, without the leading $.

final class ParamClosureThisTag extends TypedVariableTag
{
    // Own constructor adds nothing; both
    // properties below are inherited from
    // TypedVariableTag (and its parent TypedTag):

    public TypeNode $type {
        get => $this->statement->type;
    }

    public readonly string $variable;
}

This is the same shape as @param, just aimed at the closure's binding rather than its signature.

PHPStan documents @param-closure-this alongside its other callable-related tags; Psalm has no equivalent.

05 July 2026