Practical Swift Programs
Command Router
A small command router chooses the work to run from a command string.
Route a command
command_router.swift
let command =
let message: String
switch command {
case "build":
message = "building app"
case "test":
message = "running tests"
case "deploy":
message = "deploying site"
default:
message = "unknown command"
}
print(message)
let command =
let message: String
switch command {
case "build":
message = "building app"
case "test":
message = "running tests"
case "deploy":
message = "deploying site"
default:
message = "unknown command"
}
print(message)
let command =
let message: String
switch command {
case "build":
message = "building app"
case "test":
message = "running tests"
case "deploy":
message = "deploying site"
default:
message = "unknown command"
}
print(message)
command router
Many command-line tools start by reading a command name and selecting the matching action.