Pangram checker

You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.

For example:   The quick brown fox jumps over the lazy dog.



Task

Write a function or method to check a sentence to see if it is a   pangram   (or not)   and show its use.



Related tasks

   determine if a string has all the same characters
   determine if a string has all unique characters


s = "The quick brown fox jumps over the lazy dog."
println["\"$s\" is" + (isPangram[s] ? "" : " not") + " a pangram."]
 
isPangram[s] :=
{
   charSet = toSet[charList[lc[s]]]
   for c = "a" to "z"
      if ! charSet.contains[c]
         return false
 
   return true
}