Introspection for reducibles

Introspect.js

function introspect(source, alias) {
  return reducible(function(next, initial) {
    return reduce(source, function(value, result) {
      if (value === end) console.log(alias, "<<", value)
      if (isError(value)) console.log(alias, "\u26A1", value)
      result = next(value, result)
      if (isReduced(result)) console.log(alias, "\u2702", result.value)
      return result
    }, intial)
  })
}