Forcing miller to read data as string in conversion to JSON

In the following MWE echo x="1e2" | mlr --ojson cat my intention is for miller to generate a one-element JSON array containing the object {"x": "1e2"} The object actually returned (within the array) is instead {"x": 1e2} where the value is taken as a number, I guess that as a consequence of its parsing. How can I tell miller to generate the JSON object with a string for its value rather than a number? (The rationale underlying the quotation marks around '1e2' in the MWE is precisely to highlight this intention.)