Creates an absolute animation request for one named interpolable semantic value. The value must already be present in the scene when the request is compiled, and its kind must match destination. Interior samples use interpolate-value, while exact interval boundaries preserve the original source and requested destination representations. Named values use the same scheduler, easing, timing compositions, and conflict detection as Visual requests. They are not painted directly; derived Visual resolvers may consume them to determine concrete rendered geometry.

Returns #t when value is a request created by value-to.

Creates an absolute numerical transition. Finite reals interpolate normally; finite complex values interpolate their Cartesian components. It uses the same immutable scalar-value animation as value-to, but its numerical contract communicates that it is intended to drive a numeric display.

Recognizes a request created by change-number-to.

Counts from the named parameter’s value at this play clip’s start to destination. The initial named value must therefore be a compatible finite real when the request is compiled.

Recognizes a request created by count-to.

Counts between explicit endpoints. In particular, from is the value at clip phase zero even if the preceding scene has a different value. This is useful for independently reproducible counters and does not introduce a mutable tracker.

Recognizes a request created by count-from.