Class BetaReducer

Applies beta reduction on invocation expressions (applications) applied to lambda expressions (abstractions). Various expression tree rewrites can use this step to inline expressions in a template represented by a lambda expression.

Inheritance

System.Object

BetaReducer

Namespace: System.Linq.CompilerServices

Assembly: Nuqleon.Linq.CompilerServices.dll

Syntax

public static class BetaReducer : Object

Examples

Consider the following expression:

Expression.Invoke(Expression.Lambda(x, x), Expression.Constant(42))

After beta reduction, the resulting expression is:

Expression.Constant(42)

Methods

Reduce(Expression)

Applies beta reduction on invocation expressions in the given expression. Only arguments of an atomic expression node type will be inlined.

Declaration

public static Expression Reduce(Expression expression)

Parameters

Type	Name	Description
System.Linq.Expressions.Expression	expression	Expression to apply beta reductions on.

Returns

Type	Description
System.Linq.Expressions.Expression	Expression after applying beta reductions.

Reduce(Expression, BetaReductionNodeTypes, BetaReductionRestrictions)

Applies beta reduction on invocation expressions in the given expression, using the specified configuration flags. This is an advanced method which should be used with care when side-effects in expression trees are critical to maintain. Some configurations may lead to changes in timing and the arity of side-effects.

Declaration

public static Expression Reduce(Expression expression, BetaReductionNodeTypes nodeTypes, BetaReductionRestrictions restrictions)

Parameters

Type	Name	Description
System.Linq.Expressions.Expression	expression	Expression to apply beta reductions on.
BetaReductionNodeTypes	nodeTypes	Flags to restrict the argument expression node types that will be inlined during beta reduction. (Default: Atoms)
BetaReductionRestrictions	restrictions	Flags to restrict the number of uses of each argument expression during inlining. (Default: None)

Returns

Type	Description
System.Linq.Expressions.Expression	Expression after applying beta reductions.

ReduceEager(Expression, BetaReductionNodeTypes, BetaReductionRestrictions, Boolean)

Applies beta reduction on invocation expressions in the given expression, using the specified configuration flags, until no further reductions are possible. This is an advanced method which should be used with care when side-effects in expression trees are critical to maintain. Some configurations may lead to changes in timing and the arity of side-effects.

Declaration

public static Expression ReduceEager(Expression expression, BetaReductionNodeTypes nodeTypes, BetaReductionRestrictions restrictions, bool throwOnCycle)

Parameters

Type	Name	Description
System.Linq.Expressions.Expression	expression	Expression to apply beta reductions on.
BetaReductionNodeTypes	nodeTypes	Flags to restrict the argument expression node types that will be inlined during beta reduction.
BetaReductionRestrictions	restrictions	Flags to restrict the number of uses of each argument expression during inlining.
System.Boolean	throwOnCycle	Indicates whether to throw an exception if the reduction gets stuck in a cyclic reduction (e.g. for a recursive lambda expression). If set to false, the reduction stops and the current expression is returned.

Returns

Type	Description
System.Linq.Expressions.Expression	Expression after applying beta reductions.