org.overturetool.vdmj.expressions
Class LambdaExpression

java.lang.Object
  org.overturetool.vdmj.expressions.Expression
      org.overturetool.vdmj.expressions.LambdaExpression

All Implemented Interfaces:

java.io.Serializable

public class LambdaExpression
extends Expression

See Also:

Serialized Form

Field Summary

java.util.List<TypeBind>	bindList
Expression	expression

Fields inherited from class org.overturetool.vdmj.expressions.Expression

breakpoint, location

Constructor Summary

LambdaExpression(LexLocation location, java.util.List<TypeBind> bindList, Expression expression)

Method Summary

Value	eval(Context ctxt) Evaluate the expression in the given runtime context.
Expression	findExpression(int lineno) Find an expression starting on the given line.
ProofObligationList	getProofObligations(POContextStack ctxt) Get a list of proof obligations from the expression.
java.lang.String	kind() A short descriptive string for the expression.
java.lang.String	toString()
Type	typeCheck(Environment base, TypeList qualifiers, NameScope scope) Perform a type check of the expression.

Methods inherited from class org.overturetool.vdmj.expressions.Expression

abort, abort, concern, detail, detail, detail2, detail2, getPreName, report, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

bindList

public final java.util.List<TypeBind> bindList

expression

public final Expression expression

Constructor Detail

LambdaExpression

public LambdaExpression(LexLocation location,
                        java.util.List<TypeBind> bindList,
                        Expression expression)

Method Detail

toString

public java.lang.String toString()

Specified by:

toString in class Expression

typeCheck

public Type typeCheck(Environment base,
                      TypeList qualifiers,
                      NameScope scope)

Description copied from class: Expression

Perform a type check of the expression. The method returns the Type of the expression it checked, and is used recursively across an expression tree. For example, a boolean "and" expression would type check its left and right hand sides, check that the types returned were both compatible with BooleanType and then return a BooleanType (regardless of any errors).

The qualifiers argument is passed when checking function and operation application. It contains the list of argument types of the application, and is used to choose between overloaded function/operation definitions.

Specified by:

typeCheck in class Expression

Parameters:

base - The static environment for resolving names.

qualifiers - The argument type qualifiers for overloading.

scope - The scope of applicable names from the environment.

Returns:

The type of the expression.

eval

public Value eval(Context ctxt)

Description copied from class: Expression

Evaluate the expression in the given runtime context. The Value object returned can hold any type of value (int, bool, sequences, sets etc).

Specified by:

eval in class Expression

Parameters:

ctxt - The context in which to evaluate the expression.

Returns:

The value of the expression.

findExpression

public Expression findExpression(int lineno)

Description copied from class: Expression

Find an expression starting on the given line. Single expressions just compare their location to lineno, but expressions with sub-expressions iterate over their branches.

Overrides:

findExpression in class Expression

Parameters:

lineno - The line number to locate.

Returns:

An expression starting on the line, or null.

getProofObligations

public ProofObligationList getProofObligations(POContextStack ctxt)

Description copied from class: Expression

Get a list of proof obligations from the expression.

Overrides:

getProofObligations in class Expression

Parameters:

ctxt - The call context.

Returns:

The list of proof obligations.

kind

public java.lang.String kind()

Description copied from class: Expression

A short descriptive string for the expression. An example would be "forall" or "map comprehension".

Specified by:

kind in class Expression

Returns:

A short name for the expression.