Overloading the existing `toInt` method
The toInt method in StringLike doesn't take any arguments, and can only parse in decimal. So to parse binary, hex etc we need to resort to Java's Integer#parseInt(String s, int radix) .
In an attempt to remedy this state of affairs, I tried the following
implicit def strToToIntable(s: String) = new {
def toInt(n: Int) = Integer.parseInt(s, n)
}
However,
"101".toInt(2)
causes the REPL compiler to "crash spectacularly" and doesn't work in compiled code either.
Is there some restriction on overloading existing methods using the "enrich my library" pattern?
Without the implicit, running "101".toInt(2) causes REPL to tell me that Int does not take parameters. So I guess what is happening is that it's running "101".toInt , then trying to call apply(2) on that, which doesn't make sense. I'd suggest a subtle rename of your pimped toInt to avoid the problem.
edit
I just had some success of my own. I explicitly defined a pimped string class as
class StrToRadixInt(s:String) {
def toInt(radix: Int) = Integer.parseInt(s,radix)
}
implicit def strToToIntable(s:String) = new StrToRadixInt(s)
And REPL was happy:
scala> "101".toInt(2)
res4: Int = 5
The REPL shouldn't crash--that's a bug. But even so, overloading of names is somewhat discouraged and also not supported in some contexts. Just use a different name:
implicit def parseBase(s: String) = new { def base(b: Int) = Integer.parseInt(s,b) }
scala> "10110" base 2
res1: Int = 22
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