toString and Backslash in ML

Question

Say I want to represent a string in my Metalanguage, so I have a string like "String" the following code will do the following for me

I have

repl>"string"

Will output:

\"string\"

I know the problem has to do with toString, from what I have read it converts double quotes to series of backslashes, My question is there a function I can so I can just output the string normally.

Answer 1

You could try this:

| expression2string(String(X)) = X

Answer 2

I don't know what your parser does, but usually I would expect it to not include the quote characters in the string value, i.e., the x in String(x) should only contain the actual content of the string. Then you'd just define

| expression2string(String s) = "\"" ^ String.toString s ^ "\""

This escapes the string content properly (e.g. newlines or inner quotes), but not the surrounding quotes, which are language syntax, not content.