Crate zng_var

Batch updated variables in an app context.

Crate

This crate is part of the zng project.

Cargo Features

This crate provides 2 feature flags, 1 enabled by default.

"debug_default"

Signal the build script to enable the "dyn_*" features in debug builds.

Enabled by default.

"dyn_closure"

Box closures at opportune places, such as Var::map, reducing the number of monomorphised types.

This speeds-up compilation time at the cost of runtime.

Modules

• animation
  Var animation types and functions.
• types
  Other variable types.

Macros

• context_var
  Declares new ContextVar static items.
• expr_var
  New variable from an expression with interpolated vars.
• impl_from_and_into_var
  Implements T: IntoVar<U>, T: IntoValue<U> and optionally U: From<T> without boilerplate.
• merge_var
  Initializes a new Var with value made by merging multiple other variables.
• when_var
  Initializes a new conditional var.

Structs

• AnyVarHookArgs
  Arguments for AnyVar::hook_any.
• ArcEq
  Arc value that implements equality by pointer comparison.
• ArcVar
  Reference counted read/write variable.
• ContextInitHandle
  Identifies the unique context a ContextualizedVar is in.
• ContextVar
  Represents another variable in a context.
• LocalVar
  Represents a single value as Var<T>.
• MergeVarBuilder
  Build a merge-var from any number of input vars of the same type I.
• ObservableVec
  Represents a Vec<T> that tracks changes when used inside a variable.
• TraceValueArgs
  Args for Var::trace_value.
• VARS
  Variable updates and animation service.
• VARS_APP
  VARS APP integration.
• VarCapability
  Kinds of interactions allowed by a Var<T> in the current update.
• VarHandle
  Handle to a variable hook.
• VarHandles
  Represents a collection of var handles.
• VarHookArgs
  Arguments for Var::hook.
• VarIsReadOnlyError
  Error when an attempt to modify a variable without the MODIFY capability is made.
• VarModify
  Represents the current value in a Var::modify handler.
• VarPtr
  Represents an AnyVar pointer that can be used for comparison.
• VarUpdateId
  Represents the last time a variable was mutated or the current update cycle.

Traits

• AnyVar
  Methods of Var<T> that are object safe.
• AnyVarValue
  Trait implemented for all VarValue types.
• AnyWeakVar
  Represents a weak reference to an AnyVar.
• IntoValue
  A property value that is not a variable but can be inspected.
• IntoVar
  A value-to-var conversion that consumes the value.
• Var
  Represents an observable value.
• VarValue
  Represents a type that can be a Var<T> value.
• WeakVar
  Represents a weak reference to a Var<T>.

Functions

• getter_var
  Variable for getter properties (get_*, actual_*).
• response_done_var
  New ResponseVar in the done state.
• response_var
  New paired ResponderVar and ResponseVar in the waiting state.
• state_var
  Variable for state properties (is_*, has_*).
• var
  New ref counted read/write variable with initial value.
• var_default
  New ref counted read/write variable with default initial value.
• var_from
  New ref counted read/write variable with initial value converted from source.

Type Aliases

• BoxedAnyVar
  Represents a type erased boxed var.
• BoxedAnyWeakVar
  Represents a weak reference to a BoxedAnyVar.
• BoxedVar
  Represents a Var<T> boxed.
• BoxedWeakVar
  Represents a weak reference to a BoxedVar<T>.
• ReadOnlyArcVar
  Read-only ArcVar<T>.
• ReadOnlyContextVar
  Context var that is always read-only, even if it is representing a read-write var.
• ResponderVar
  Variable used to notify the completion of an async operation.
• ResponseVar
  Variable used to listen to a one time signal that an async operation has completed.