| Inform7 - an interactive fiction language - is often instructive in suggesting different approaches to syntax from those used in mainstream programming, and indeed in this case it has a couple of interesting constructions to avoid naked Booleans. Most directly relevant to this, it has the concept of ‘options’ as arguments to ‘phrases’ (which are basically functions). This would let you write something like: to decide what number is the calculated formula for (a: a number) and (b: a number), with gain or without gain
And within the function you could use ‘with gain’ and ‘without gain’ as if they were booleans: If with gain, decide on a+b;
And at the calling site you would call the function like so: Let c be the calculated formula for 3 and 4, with gain
(http://inform7.com/book/WI_11_14.html)Obviously in Inform7 you are more likely to be using this in a much more naturalistic way, effectively adding ‘adverbs’ to the ‘verbs’ your phrases are defining: To recount the story so far, cursorily or in great detail…
Another similar Inform language feature is its mechanism for Boolean properties.You can declare a Boolean property on a ‘kind’ or a ‘thing’ just by saying that it ‘can’ be true: A chair can be comfy.
The table can be scratched.
You can also use ‘either/or’ forms to make these booleans richer and more expressive: A chair can be comfy or hard.
(You can also go on and add more values, of course - at this point it’s really an enumeration)These sorts of properties on kinds become ‘adjectives’, and you can use them in both declarations: The overstuffed armchair is a comfy chair in the living room.
And in expressions: If the target is a comfy chair…
The idea that Boolean parameters are really adverbs and Boolean properties are really adjectives I think says something quite profound, and there’s definitely room for other languages to do better at acknowledging the first-class role these kinds of constructs could have with the right syntax. |