Open Radar

 
In Swift, it should be possible to declare variables with the keyword 'say', so that the ways of specifying constants and variables use the same parts of speech.

I love the way you guys resurrected "let" from Dylan. It's very clear that it means you're setting up initial conditions like you would in a mathematical proof. But it looks jarring next to "var" because one is a verb and the other is a noun or adjective. Compare:

let x = 0
var y = 1

vs...

let x = 0
say y = 1

People have used the word "say" to describe arbitrary values in thought experiments for a long time. Wikipedia dates it back to at least Galileo in 1638: "But if this is true, and if a large stone moves with a speed of, say, eight" (http://en.wikipedia.org/wiki/Thought_experiment)

Or consider one of the definitions for 'say' in the Mac OS X built-in dictionary: "used parenthetically to indicate that something is being suggested as possible or likely but not certain"

"Let X equal 0, and say y equals 1" rolls trippingly off the tongue like natural language, and uses words that clearly convey one item is a constant while the other is an arbitrary value. Whereas "Let X equal 0, and var y equals 1" only makes sense if you simply consider let and var as compiler keyword nouns with human-friendly adjectives describing them, stripping away the conventional power of "let" as a verb. That means an extra level of thought is necessary to convert those keywords back into meaning.