package com.jclark.xsl.expr;

import com.jclark.xsl.om.*;

class RoundFunction extends Function1 {
  ConvertibleExpr makeCallExpr(ConvertibleExpr e) throws ParseException {
    final NumberExpr ne = e.makeNumberExpr();
    return new ConvertibleNumberExpr() {
      public double eval(Node node, ExprContext context) throws XSLException {
	double n = ne.eval(node, context);
	double r = Math.floor(n + 0.5);
	if (r == 0.0 && n < 0.0)
	  return -r; // round(-0.2) returns -0 not 0
	return r;
      }
    };
  }
}