Surroundwith - vilinski/nemerle GitHub Wiki

The surroundwith macro is macro which can help you to emulate "using"-like behavior.

You can define surround by DefineSurround macro and use name (defined by DefineSurround) in surroundwith.

The DefineSurround macro has the following parameters:

• name - name of defined surround (string)
• useTryFinally - when true, try/finally expression is generated for each surroundwith.
• beforeExpr - expression to add before surrounded expression
• afterExpr - expression to add after surrounded expression

Following example demonstrates the usage of this macro:

using System.Console;
using Nemerle.Surround;

[assembly: DefineSurround("surround1", false, WriteLine("Surround1Before"), WriteLine("Surround1After"))]
[assembly: DefineSurround("surround2", false, WriteLine("Surround2Before"), WriteLine("Surround2After"))]
[assembly: DefineSurround("surround3", false, WriteLine("Surround3Before"), WriteLine("Surround3After"))]

module Test
{
  Main() : void
  {
    surroundwith (surround1, surround2, surround3)
      WriteLine("Test1");

    WriteLine();

    surroundwith (surround1)
      WriteLine("Test2");

    WriteLine();

      surroundwith (surround1)
    surroundwith (surround2)
      WriteLine("Test3");

  }
}

Surround1Before
Surround2Before
Surround3Before
Test1
Surround3After
Surround2After
Surround1After

Surround1Before
Test2
Surround1After

Surround1Before
Surround2Before
Test3
Surround2After
Surround1After