Freya: "lock" statements

The lock statement obtains a mutual exclusion lock for a given object, executes a statement, and then releases the lock

Syntax

This is the syntax for the lock statement:

lock expression then
    statement

The expression in the lock statement header must evaluate to a reference type. It is translated like this:

System.Threading.Monitor.Enter(expression);
try
    statement;
finally
    System.Threading.Monitor.Exit(expression);
end;

The expression is evaluated only once, and a local variable may be declared if needed, to ensure this behavior.