lib/install.js
function isValid (path, entry) {
        var isValid = valid(path)
        if (isValid) {
          log.verbose('extracted file from tarball', path)
          extractCount++
        } else {
          // invalid
          log.silly('ignoring from tarball', path)
        }
        return isValid
      }
function isValid (path, entry) {
        var isValid = valid(path)
        if (isValid) {
          log.verbose('extracted file from tarball', path)
          extractCount++
        } else {
          // invalid
          log.silly('ignoring from tarball', path)
        }
        return isValid
      }
function isValid ( path , entry ) { var isValid = valid ( path ) if ( isValid ) { log . verbose ( 'extracted file from tarball' , path ) extractCount ++ } else { // invalid log . silly ( 'ignoring from tarball' , path ) } return isValid }
checks if a file to be extracted from the tarball is valid. only .h header files and the gyp files get extracted
checks if a file to be extracted from the tarball is valid . only . h header files and the gyp files get extracted