Assign.java

/**
 * $Id: $
 * $Date: $
 *
 */

package org.xmlsh.sh.core;

import static org.xmlsh.util.Util.hasAnyChar;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.EnumSet;
import org.xmlsh.core.CoreException;
import org.xmlsh.core.EvalEnv;
import org.xmlsh.core.InvalidArgumentException;
import org.xmlsh.core.XValue;
import org.xmlsh.core.XVariable;
import org.xmlsh.core.XVariable.XVarFlag;
import org.xmlsh.sh.shell.Shell;
import org.xmlsh.types.TypeFamily;
import org.xmlsh.types.xtypes.XValueArray;
import org.xmlsh.types.xtypes.XValueMap;
import org.xmlsh.types.xtypes.XValuePropertyList;
import org.xmlsh.types.xtypes.XValueSequence;

public class Assign {

  private static final EvalEnv mListVarEnv = EvalEnv.newInstance(false, true,
      false, false);
  private static final EvalEnv mSingleVarEnv = EvalEnv.basicInstance();
  private boolean mLocal = false;
  private String mVariable;
  private String mOp;		// "=" or "+-"
  private Word mInd;      // [ index ]
  private Word mRValue;		// a single value a=b
  private WordList mRValList; // a sequence constructor a=(b)
  private String mTypeStr;  // =[ =( ={

  public Assign(boolean local, String typeStr, String variable, String op,
      Word rvalue) {
    mLocal = local;
    mTypeStr = typeStr;
    mVariable = variable;
    mOp = op;
    mRValue = rvalue;

  }

  public Assign(boolean local, String typeStr, String variable, Word ind,
      String op, Word rvalue) {
    mLocal = local;
    mTypeStr = typeStr;
    mVariable = variable;
    mOp = op;
    mInd = ind;
    mRValue = rvalue;
  }

  public Assign(boolean local, String typeStr, String variable, String op,
      WordList rvalue) {
    mLocal = local;
    mTypeStr = typeStr;
    mVariable = variable;
    mOp = op;
    mRValList = rvalue;
  }

  public void print(PrintWriter out) {
    if(mLocal)
      out.print("local ");
    out.print(getVariable());
    if(mInd != null) {
      out.print("[");
      mInd.print(out);
      out.print("]");

    }
    out.print(mOp);
    if(mRValue != null)
      mRValue.print(out);
    else {
      out.print("(");
      boolean bFirst = true;
      if(mRValList != null)
        for(Word w : mRValList) {
          if(!bFirst)
            out.print(" ");
          w.print(out);
          bFirst = false;

        }
      out.print(")");

    }
    out.print(" ");

  }

  public String getOp() {
    return mOp;
  }

  public String getVariable() {
    return mVariable;
  }

  public boolean isLocal() {
    return mLocal;
  }

  public void eval(Shell shell, SourceLocation loc)
      throws IOException, CoreException {

    XValue value = null;

    if(mRValue == null && mRValList == null)
      value = nullValue(mTypeStr);

    // Eval RHS
    else if(mRValue != null)
      // Single variables dont expand wildcards
      value = mRValue.expand(shell, mSingleVarEnv);
    else if(mRValList != null)
      // Sequences expand wildcards
      value = mRValList.expand(shell, mListVarEnv, loc);

    // Assign
    if(getOp().equals("+="))
      shell.getEnv().appendVar(getVariable(), value);
    else {

      if(mInd != null) {
        String ind = mInd.expandString(shell, mListVarEnv);
        shell.getEnv().setIndexedVar(getVariable(), value, ind);
      }
      else if(mLocal)
        shell.getEnv().declareVar(getVariable(), XVariable.localFlags(), value);
      else
        shell.getEnv().setVar(getVariable(), value);
    }

  }

  private XValue nullValue(String typeStr) throws InvalidArgumentException {
    switch(typeStr){
    case "=":
    case "+=":
      return XValue.nullValue();
    case "[]":
      return XValue.newXValue(TypeFamily.XTYPE, XValueArray.emptyArray());
    case "{}":
      return XValue.newXValue(TypeFamily.XTYPE,
          XValueMap.emptyMap());
    case "()":
      return XValue.newXValue(TypeFamily.XTYPE, XValueSequence.emptySequence());
    }
    return XValue.nullValue();
  }

}

//
//
// Copyright (C) 2008-2014 David A. Lee.
//
// The contents of this file are subject to the "Simplified BSD License" (the
// "License");
// you may not use this file except in compliance with the License. You may
// obtain a copy of the
// License at http://www.opensource.org/licenses/bsd-license.php
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is David A. Lee
//
// Portions created by (your name) are Copyright (C) (your legal entity). All
// Rights Reserved.
//
// Contributor(s): none.
//