module Roda::RodaPlugins::SymbolMatchers

  1. lib/roda/plugins/symbol_matchers.rb

The symbol_matchers plugin allows you do define custom regexps to use for specific symbols. For example, if you have a route such as:

r.on :username do |username|
  # ...

By default this will match all nonempty segments. However, if your usernames must be 6-20 characters, and can only contain a-z and 0-9, you can do:

plugin :symbol_matchers
symbol_matcher :username, /([a-z0-9]{6,20})/

Then the route will only if the path is /foobar123, but not if it is /foo, /FooBar123, or /foobar_123.

By default, this plugin sets up the following symbol matchers:


/(\d+)/, a decimal segment


/(.*)/, all remaining characters, if any


/(\w+)/, a alphanumeric segment

If the placeholder_string_matchers plugin is loaded, this feature also applies to placeholders in strings, so the following:

r.on "users/:username" do |username|
  # ...

Would match /users/foobar123, but not /users/foo, /users/FooBar123, or /users/foobar_123.

If using this plugin with the params_capturing plugin, this plugin should be loaded first.


Public Class

  1. configure
  2. load_dependencies

Public Class methods

[show source]
   # File lib/roda/plugins/symbol_matchers.rb
45 def self.configure(app)
46   app.symbol_matcher(:d, /(\d+)/)
47   app.symbol_matcher(:w, /(\w+)/)
48   app.symbol_matcher(:rest, /(.*)/)
49 end
[show source]
   # File lib/roda/plugins/symbol_matchers.rb
41 def self.load_dependencies(app)
42   app.plugin :_symbol_regexp_matchers
43 end