patterns in Jester are very slow

[decig726]

patterns in Jester are very slow compared to normal routes
i mean by more than half when i benchmark with wrk
that should be negligible
get "/hello/@name":
let val = @"name"
resp val

[jfilby]

I took a look at patterns.nim and in the check() function found this line of code:

return s.substr(i, cutTo) == n.text

This means that a partial copy of a string is made every time the check() function is called. For better performance a string comparison function should be used instead (zero-copy). In C I would use strncmp starting at position i with the length of cutTo, but as I'm new to Nim I'm not sure what the best way to do this is (string slices don't appear to be zero-copy from my research).

[Araq]

Zero-copy string slices for Nim are in the works though.

[tuffnatty]

strutils.continuesWith() seems to fit.