I had that problem with XML. Now I do not use XML myself, but I wrote a tool to load it and convert some values to boolean. I wrote it to read true/false, but

I had that problem with XML. Now I do not use XML myself, but I wrote a tool to load it and convert some values to boolean. I wrote it to read true/false, but then there were some test cases that failed. Turns out, the schema also allows yes/no and 1/0 as synonyms.