examples/excerpt.js
function firstFourLines(file, options) {
  file.excerpt = file.content.split('\n').slice(0, 4).join(' ');
}
function firstFourLines(file, options) {
  file.excerpt = file.content.split('\n').slice(0, 4).join(' ');
}
function firstFourLines ( file , options ) { file . excerpt = file . content . split ( '\n' ) . slice ( 0 , 4 ) . join ( ' ' ) ; }
excerpt as a function returns the first 4 lines of the contents
excerpt as a function returns the first 4 lines of the contents