On 27/06/16 2:39 AM, Daniel Díaz wrote:
In the "text" package, the signature of Data.Text.replace http://hackage.haskell.org/package/text-1.2.2.1/docs/Data-Text.html#v:replac... always sends me looking into the haddocks:
replace :: Text-> Text -> Text-> Text
Which argument is the text to replace, which is the replacement and which is the text that should be scanned?
Considering partial application, the order that makes the most sense is - what to look for - what to replace it with - the big string to search and replace in I've never used this function. Let's go look at the documentation. Pats self on back: nailed it.
Imagine a generalized version of replace that 1) works on streams, and 2) allows replacing a sequence of texts (like, say, chapter headers) instead of replacing the same text repeatedly. It could have the following signature:
replace' :: Stream (Stream (Of Text) m) m () -> Stream (Stream (Of Text) m) m Void -> Stream (Of Text) m r -> Stream (Of Text) m r
Do you find easy to intuit, just by looking at that signature, which is the function of each argument?
Absolutely not. In fact, this crossed my personal complexity horizon and is still accelerating towards some kind of singularity. The more I try to imagine a problem that this might be a solution to, the less I can understand why it would be approached this way. To be perfectly honest, I've never found replacing one string by another to be terribly useful. Replacing one *token sequence* by another, yes. Replacing a (match for a) regular expression by a derived string, yes.