signal

import "github.com/rfwlab/rfw/v2/state"

Fine-grained reactive values. Re-exported from composition/types via the state package.

NewSignal

func NewSignal[T any](initial T) *Signal[T]

Creates a signal with the given initial value.

Signal[T]

Method	Description
`Get() T`	Returns current value. Tracks in `Effect` if called inside one. Nil-safe: returns zero value on nil receiver.
`Set(value T)`	Updates value and re-runs dependent effects. Nil-safe: no-op on nil receiver.
`Read() any`	Returns current value as `any`. Nil-safe: returns nil on nil receiver.
`OnChange(fn func(T)) func()`	Registers a change listener. Returns unsubscribe function. Nil-safe: returns no-op on nil receiver.
`Channel() <-chan T`	Returns a channel that receives new values. Nil-safe: returns nil channel on nil receiver.
`SetFromHost(v any)`	Updates value from a host (server-side) payload. Handles JSON float64→int conversion.

Nil Safety

All Signal[T] methods handle nil receivers gracefully — no panics. This is important when signals are accessed before composition.New initializes them, or in server-side rendering contexts.

Effect

func Effect(fn func() func()) func()

Re-runs fn whenever any signal read inside it changes. Returns a stop function.

Pre-aliased Types

Type	Definition	Constructor
`Int`	`Signal[int]`	`NewInt(v int) *Int`
`String`	`Signal[string]`	`NewString(v string) *String`
`Bool`	`Signal[bool]`	`NewBool(v bool) *Bool`
`Float`	`Signal[float64]`	`NewFloat(v float64) *Float`
`Any`	`Signal[any]`	`NewAny(v any) *Any`

Host Signal Types

Type	Definition	Use
`HInt`	`*Signal[int]`	SSC host-synced integer
`HString`	`*Signal[string]`	SSC host-synced string
`HBool`	`*Signal[bool]`	SSC host-synced boolean
`HFloat`	`*Signal[float64]`	SSC host-synced float
`HSlice[T]`	`*Signal[[]T]`	SSC host-synced slice
`HMap[K,V]`	`*Signal[map[K]V]`	SSC host-synced map

Host signal types embed *Signal[T] and additionally register as host component bindings in composition.New.