.expr (Choose Expression Evaluator)

The .expr command specifies the default expression evaluator.

.expr /s masm 
.expr /s c++ 
.expr /q 


/s masm
Changes the default expression type to Microsoft Assembler expression evaluator (MASM). This type is the default value when you start the debugger.

/s c++
Changes the default expression type to the C++ expression evaluator.

Displays the list of possible expression types.



User mode, kernel mode


Live, crash dump




When you use the .expr command without an argument, the debugger displays the current default expression type.

The ?? (Evaluate C++ Expression) command, the

Watch window, and the Locals window always use C++ expression syntax. All other commands and debugging information windows use the default expression evaluator.

For more information about how to control which syntax is used, see Evaluating Expressions. For more information about the syntax, see Numerical Expression Syntax.

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