It is important to remember that ColdFusion always evaluates function arguments before the argument values are passed to a function:

For example, consider the following DE function:

<cfoutput>#DE("1" & "2")#</cfoutput>

You might expect this line to display """1"" & ""2""". Instead, it displays "12", because ColdFusion processes the line as follows:

1. Evaluates the expression "1" & "2" as the string "12".
2. Passes the string "12" (without the quotation marks) to the DE function.
3. Calls the DE function, which adds literal quotation marks around the 12.

Similarly, if you use the expression DE(1 + 2), ColdFusion evaluates 1 + 2 as the integer 3 and passes it to the function. The function converts it to a string and surrounds the string in literal quotation marks: "3".