scenic.core.lazy_eval

Support for lazy evaluation of expressions and specifiers.

Summary of Module Members

Functions

makeDelayedFunctionCall	Utility function for creating a lazily-evaluated function call.
makeDelayedOperatorHandler
needsLazyEvaluation
requiredProperties
toDelayedArgument
valueInContext	Evaluate something in the context of an object being constructed.

Classes

DelayedArgument	Specifier arguments requiring other properties to be evaluated first.
LazilyEvaluable	Values which may require evaluation in the context of an object being constructed.

Member Details

class LazilyEvaluable(requiredProps)

Bases: object

Values which may require evaluation in the context of an object being constructed.

If a LazilyEvaluable specifies any properties it depends on, then it cannot be evaluated to a normal value except during the construction of an object which already has values for those properties.

evaluateIn(context)

Evaluate this value in the context of an object being constructed.

The object must define all of the properties on which this value depends.

evaluateInner(context)

Actually evaluate in the given context, which provides all required properties.

class DelayedArgument(requiredProps, value)

Bases: scenic.core.lazy_eval.LazilyEvaluable

Specifier arguments requiring other properties to be evaluated first.

The value of a DelayedArgument is given by a function mapping the context (object under construction) to a value.

makeDelayedFunctionCall(func, args, kwargs)

Utility function for creating a lazily-evaluated function call.

valueInContext(value, context)

Evaluate something in the context of an object being constructed.