AlphabeticallyByPart returns a byPartAlphabetical that will sort 'metrics' alphabetically by 'part'.

EvalExpr is the main expression evaluator.

FetchAndEvalExp fetch data and evaluates expressions.

NewEvaluator create evaluator with limiter and zipper.

RewriteExpr expands targets that use applyByNode into a new list of targets.

SortMetrics sort metric data alphabetically.