Last night I found myself wrestling with the behavior of ColdFusion's JSON serializing where the strings "yes" and "no" are converted to a Boolean and come out the other side as "true" and "false". This happens when variables are passed through SerializeJSON(), or a CFC is called with returnFormat="json". Nathan Mische pointed out not too long ago that 1 and 0 are NOT converted to Booleans, which is interesting.
I have a feeling the logic goes something like this:
2 Treat it as a number
3 Else if it can be converted to a Boolean
4 Treat it as a Boolean
6 Treat it as a string
1's and 0's probably get picked off early that way. As annoying as it is though, I'm not sure what the better solution would be. Unfortunately, in a loosely typed language the server has to make guesses for you that can be kind of un-forgiving when you translate them to a strictly typed language.
In my case, I was passing back a result set to be bound to a cfgrid, so I didn't really have much control of how it displayed once it left the server. I needed it to come back from the server in the correct format.
My solution was to add a space before or after each word such as "yes " and "no ". It's not quite optimal, but it works. The results were left as string and made it safely back to the browser.
As far as a work-around from Adobe, I had originally thought of adding an additional setting called strictBooleanParsing or something, but what worked for one person would probably never work for someone else. In the end, it might have been best for them to ONLY accept "true" and "false" as Booleans. I don't think that would be too much to ask programmers to do.
I mean, it's nice that you can be all loosey-goosey inside of ColdFusion with your data types, but I wouldn't expect that same kind of freedom when I want to convert my data to a less forgiving format. This might never be changed though given the backwards compatibility issue. There is probably code out there now that depends on "yes" and "no" turning Boolean. What would your solution be?