Exception handling in Swift.

Example.swift

import Foundation


let (succ: String?, err: NSException?) = try {
    NSException(name: "ExceptionTest", reason: "Exception reason", userInfo: nil).raise()
    return "Foobar"
}

if succ {
    println("Success: \(succ)")
} else if err {
    println("Error [\(err!.name)]: \(err!.reason)")
}

Try.swift

import Foundation


func try<T>(block: () -> T) -> (T?, NSException?) {
    var result: (T?, NSException?) = (nil, nil)
    tryWithBlock__({ result = (block(), nil) }, { result = (nil, $0) })
    return result
}

TryResult.h

#import <Foundation/Foundation.h>


void tryWithBlock__(void (^block)(void), void (^failure)(NSException *));

TryResult.m

#import "TryResult.h"


void tryWithBlock__(void (^block)(void), void (^failure)(NSException *)) {
    @try {
        block();
    }
    @catch (NSException *exception) {
        failure(exception);
    }
}