String Substitution Utilities

Substituting using a method

This function operates in just the same way as substFirst. However, this function has been implemented as a method and added to the string class. Instead of calling a function such as myFunction("foo"), a method looks like a property with arguments, e.g., "foo".myFunction(). The procedure to add a method to the String class will change in the next version of Netscape Navigator (code-named "Atlas"). Instead of adding methods to the empty string, you will need to add the methods to the class String.

Warning: Adding string methods is *broken* in Atlas PR1, although it should work with Atlas PR2 and later. 

// Same as substFirst but as a string method
function subst1(c1, c2)
{
	if (this == "") return this
	
	// find the character string
	var i = this.indexOf(c1)
	
	// return original string if not found
	if (i < 0) return this
	
	// extract the characters before and after the string
	var s1 = (""+this).substring(0, i)
	var s2 = (""+this).substring(i+1, this.length)
	return s1+c2+s2
}

// Add to the string class
String.subst1 = subst1

// For early versions of navigator
"".subst1 = subst1
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