diegogub

Ring handler a function which accepts a request (map) and returns a response (map).

Ring middleware

function (handler, &args -> function(request -> response) because it is a closure handler and &args are in scope within the returned handler function.

a function which accepts a "next handler" (the next handler in the chain) + any extra arguments and returns a handler (function), which will accept a request and return a response.

diegogub

unless ARGV.size > 0
  puts "  Missing executable file argument"
  puts "  Usage (in a Dockerfile)"
  puts "  RUN crystal run ./path/to/list-deps.cr -- ./bin/executable"
  exit 1
end

executable = File.expand_path(ARGV[0])

unless File.exists?(executable)