weka.core.expressionlanguage.core

Interface MacroDeclarations

All Known Implementing Classes:

IfElseMacro, InstancesHelper, JavaMacro, MacroDeclarationsCompositor, MathFunctions, NoMacros

public interface MacroDeclarations

Interface to expose macros to a program.

It is deliberately kept very simple to give as little constraints as possible to implementations.

There is an implied invariant here:
hasMacro(String) == true -> getMacro(String) != null

hasMacro(String) should be pure i.e. have no side effects.
Whereas getMacro(String) may have side effects.
(This is useful for creating macros on the fly in getMacro(String))

Version:

$Revision: 1000 $

Author:

Benjamin Weber ( benweber at student dot ethz dot ch )

Method Summary

Modifier and Type	Method and Description
Macro	getMacro(String name) Tries to fetch the macro
boolean	hasMacro(String name) Whether the macro is declared

Method Detail

hasMacro

boolean hasMacro(String name)

Whether the macro is declared

Parameters:

name - name of the macro being queried

Returns:

whether the macro is declared

getMacro

Macro getMacro(String name)

Tries to fetch the macro

Before a macro is fetched it shold be checked whether it is declared through hasMacro(String)

Parameters:

name -

Returns: