Groovy Name-and-Value Macro Support Proposal - Code

[MG]

Below is the source for the proposed NV etc macros + an explanation how 
to use macros with IntelliJ IDE.

To build and use macros inside the same IntelliJ project:
1. In a Groovy 2.5 project, create a new module for the macro code
   (e.g. groovy_macro) and one for the macro usage (e.g. groovy_macro_use).
2. In groovy_macro\src (folder marked as Sources Root)
    1. Add \main\groovy\groovyx\macro\NameAndValueMacros.groovy (see below)
    2. Add \main\groovy\groovyx\NameAndValue.groovy
3. In groovy_macro\resources (folder marked as Resources Root)
    1. Add
       resources\META-INF\groovy\org.codehaus.groovy.runtime.ExtensionModule
4. Add a depency to groovy_macro to groovy_macro_use
5. Use NV/NVL in code in Groovy code in groovy_macro module (example:
   See NameAndValueMacrosTest.groovy below)

Note: As Paul already pointed out, compiling the macro code in the same 
step as the code that uses it does not work - the compiled macro code 
already needs to be on the classpath during compilation, which is why we 
need two seperate modules inside the same project. Of course the macro 
code can also be compiled independently and the resulting JAR added to 
the "groovy_macro_use" module.

Cheers,
mg


// resources\META-INF\groovy\org.codehaus.groovy.runtime.ExtensionModule

moduleName=groovy-macro-ext moduleVersion=0.1.0 
extensionClasses=main.groovy.groovyx.macro.NameAndValueMacros


// src\main\groovy\groovyx\NameAndValue.groovy

package main.groovy.groovyx

class NameAndValue {
  final Stringname final val NameAndValue(String name, val) {
    this.name = name
    this.val = val
  }

  @Override public String toString() {
    final String valStr = ((val instanceof String) || (val instanceof GString)) 
?"\"$val\"" :val.toString()
    return "$name=$valStr" }
}


// src\main\groovy\groovyx\macro\NameAndValueMacros.groovy

package main.groovy.groovyx.macro

import main.groovy.groovyx.NameAndValue
import org.codehaus.groovy.ast.ClassHelper
import org.codehaus.groovy.ast.ClassNode
import org.codehaus.groovy.ast.expr.Expression
import org.codehaus.groovy.ast.expr.GStringExpression
import org.codehaus.groovy.ast.expr.ListExpression
import org.codehaus.groovy.macro.runtime.Macro import 
org.codehaus.groovy.macro.runtime.MacroContext

import static org.codehaus.groovy.ast.tools.GeneralUtils.*

class NameAndValueMacros {

  // Expose through GeneralUtils ? static ClassNode classNode(final Class 
clazz) {
    ClassHelper.makeCached(clazz)
  }

  // NVL: NameAndValueList @Macro public static Expression NVL(MacroContext 
ctx, Expression... exps) {
    final List nvExpList = exps.collect {NV(ctx,it) }
    new ListExpression(nvExpList)
  }

  // NV: NameAndValue @Macro public static Expression NV(MacroContext ctx, 
Expression exp) {
    ctorX(classNode(NameAndValue),args(constX(exp.text), exp) )
  }

  // NVGS: NameAndValue-GString @Macro public static Expression 
NVGS(MacroContext ctx, Expression... exps) {
    final List<Expression> expList = Arrays.asList(exps)
    int i=-1 final List<Expression> nameList = expList.collect { i++;constX((i >0 ?", " 
:"") + it.text +"=") }

    final quoteCharExp =constX('"')

    final List<Expression> quoteIfStringExpList = expList.collect {final 
Expression exp ->
      final quotedExp =new 
GStringExpression('verbatimExp',[quoteCharExp,quoteCharExp],[exp])
      
ternaryX(orX(isInstanceOfX(exp,classNode(String)),isInstanceOfX(exp,classNode(GString))),
 quotedExp, exp)
    }

    new GStringExpression('', nameList, quoteIfStringExpList)
  }
}



// NameAndValueMacrosTest.groovy

package main.groovy.groovyx.macro

import groovy.transform.CompileStatic import main.groovy.groovyx.NameAndValue
import org.junit.Ignore import org.junit.Test class NameAndValueMacrosTest {
  @Test @Ignore @CompileStatic void NVL_LongVarNameTest() {
    final ageOfTree =124 final towerHeight =987.654 final String visitorName ="abc" final s1 ="DEFGH" final gs0 
="val0:$ageOfTree" final GString gs1 ="TheTower($towerHeight)" final List names = 
["Peter","Ann","Raymond" ]

    println"var0=$var0, var1=$var0" println"single variables: ${NV(ageOfTree)}and 
${NV(gs0)}and ${NV(visitorName)}and ${NV(s1)}and ${NV(gs1)}and also ${NV(names)})}" 
println"variable list: ${NVL(ageOfTree, gs0, visitorName, s1, towerHeight, gs1, names)}" }
}