IronRuby.Compiler.Ast.AstGenerator.DebugMarker C# (CSharp) Method

        internal MSA.Expression DebugMarker(string/*!*/ marker) {
            return _debugCompiler ? Methods.X.OpCall(AstUtils.Constant(marker)) : null;
        }

        // see Ruby Language.doc/Runtime/Control Flow Implementation/Yield
        internal override MSA.Expression/*!*/ TransformRead(AstGenerator/*!*/ gen) {
            MSA.Expression bfcVariable = gen.CurrentScope.DefineHiddenVariable("#yielded-bfc", typeof(BlockParam));
            MSA.Expression resultVariable = gen.CurrentScope.DefineHiddenVariable("#result", typeof(object));
            
            MSA.Expression postYield;

            if (gen.CompilerOptions.IsEval) {
                // eval:
                postYield = Methods.EvalYield.OpCall(gen.CurrentScopeVariable, bfcVariable, resultVariable);
            } else if (gen.CurrentBlock != null) {
                // block:
                postYield = Methods.BlockYield.OpCall(gen.CurrentScopeVariable, gen.CurrentBlock.BfcVariable, bfcVariable, resultVariable);
            } else {
                // method:
                postYield = Methods.MethodYield.OpCall(gen.CurrentScopeVariable, bfcVariable, resultVariable);
            }

            return new AstBlock {
                gen.DebugMarker("#RB: yield begin"),

                Ast.Assign(bfcVariable, Methods.CreateBfcForYield.OpCall(gen.MakeMethodBlockParameterRead())),

                Ast.Assign(
                    resultVariable, 
                    (Arguments ?? Arguments.Empty).TransformToYield(gen, bfcVariable, gen.MakeMethodBlockParameterSelfRead())
                ),

                AstUtils.IfThen(postYield, gen.Return(resultVariable)),

                gen.DebugMarker("#RB: yield end"),

                resultVariable
            };
        }