Synopsis Count words in a line.
Examples We count words using a regular expression match in a for loop. Each time that the pattern /[a-zA-Z0-9_]+/ matches, the body of the loop is executed and count is incremented.
module demo::common::WordCount::CountInLine1

public int countInLine1(str S){
  int count = 0;
  for(/[a-zA-Z0-9_]+/ := S){
       count += 1;
  return count;
Let's try it:
rascal>import demo::common::WordCount::CountInLine1;
rascal>countInLine1("Jabberwocky by Lewis Carroll");
int: 4
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