sample1.js

  var mylib = (function() {
    var api = {
      provide: function(name, fn) {
        this[name] = fn;
      }
    };
    ...
    api.provide('foo', function() {
      ...
    });
    api.provide('bar', function() {
      ...
    });
 
    return api;
  })();

sample2.js

  ..
  function guard(fn) {
    return function() {
      try {
        return fn.apply(this, arguments);
      } catch (e) {
        // log error
      }
    };
  }
  var api = {
    provide: function(name, fn) {
      this[name] = guard(fn);
    }
  };
  ..

sample3.js

  var ManagedError = function(message) {
    Error.prototype.constructor.apply(this, arguments);
    this.message = message;
  };
  ManagedError.prototype = new Error();

  function guard(fn) {
    return function() {
      try {
        return fn.apply(this, arguments);
      } catch (e) {
        if (e instanceof ManagedError) {
          throw e;
        }
        // log error
      }
    };
  }
  ... 
  api.provide('foo', function(...) {
    ....
    throw new ManagedError('Invalid argument');
  });

sample4.js

  ...

  function unguard(fn) {
    return function() {
      try {
        return fn.apply(this, arguments);
      } catch (e) {
        // surface the error 
        setTimeout(function() { throw e; }, 0);
      }
    };
  }

  function guard(fn) {
    // Helper function for wrapping all functions
    function wrap(fn, value) {
      // not all 'function's are actually functions!
      if (typeof value === 'function' && /^function/.test(value.toString)) {
        return fn(value);
      } else if (typeof value === 'object' && value !== null) {
        for (var key in value) if (value.hasOwnProperty(key)) {
          value[key] = wrap(fn, value[key]);
        };
      }
      return value;
    }

    return function() {
      // capture the arguments and unguard any functions
      var args = Array.prototype.slice.call(arguments)
        .map(function(arg) {
          return wrap(unguard, arg);
        });

      try {
        return fn.apply(this, args);
      } catch (e) {
        if (e instanceof ManagedError) {
          throw e;
        }
        // log error
      }
    };
  }

  ...

sample5.js

  function guard(fn) {
    // Helper function for wrapping all functions
    function wrap(fn, value) {
      // not all 'function's are actually functions!
      if (typeof value === 'function' && /^function/.test(value.toString)) {
        return fn(value);
      } else if (typeof value === 'object' && value !== null) {
        for (var key in value) if (value.hasOwnProperty(key)) {
          value[key] = wrap(fn, value[key]);
        };
      }
      return value;
    }

    return function() {
      // capture the arguments and unguard any functions
      var args = Array.prototype.slice.call(arguments)
        .map(function(arg) {
          return wrap(unguard, arg);
        });

      try {
        return wrap(unguard, fn.apply(this, args));
      } catch (e) {
        if (e instanceof ManagedError) {
          throw e;
        }
        // log error
      }
    };
  }