But it is still worth sending this in as a suggestion.
Often the hardest part of writing material which is meant
to be read by people of different backgrounds is figuring
out when language will be potentially unclear to your
target audience. While anyone with a math background would
pick up what "all" was supposed to mean from the word
"intersection", the description of intersection itself is
ambiguous and shouldn't be.
However the usual way of talking in math would suggest
one of the following two:
- by returning a list of keys that occur in every
hash passed to it.
- by returning a list of keys that occur in all
hashes passed to it.
I believe that these should be clear to people without
familiarity with the math, and also be clearer to people
for whom English is a second language.