Workaround for mashup of compile-time types

spec/helpers/matchers_helper.cr

@@ -0,0 +1,23 @@
+# Retrieves a value from the `NamedTuple` returned by `Spectator::Matchers::MatchData#values`.
+def match_data_value(match_data, key, t : T.class) forall T
+  match_data.values.fetch(key) { raise "#{key} is missing" }.as(T)
+end
+
+# Retrieves the string representation and base value
+# from a `Spectator::Matchers::PrefixedValue`
+# in a `NamedTuple` returned by `Spectator::Matchers::MatchData#values`.
+def match_data_prefix(match_data, key, t : T.class) forall T
+  prefix = match_data_value(match_data, key, Spectator::Matchers::PrefixGrabber.get(t))
+  {to_s: prefix.to_s, value: prefix.value}
+end
+
+# Dirty cheat to get around visibility restriction.
+module Spectator::Matchers
+  module PrefixGrabber
+    extend self
+
+    def get(t : T.class) forall T
+      PrefixedValue(T)
+    end
+  end
+end