Reconstruct and merge ordered inputs without general sorting

binding.go

@@ -3,7 +3,6 @@ package commandkit
 import (
 	"errors"
 	"fmt"
-	"sort"
 	"strconv"
 
 	commandmeta "go.maximumdirect.net/commandkit/internal/commandmeta"
@@ -298,7 +297,14 @@ func prepareInputWithOccurrences[I any](spec CommandSpec[I], flagValues, flagSpe
 				fallbackOrdinal++
 			}
 			if occurrence.apply != nil {
-				ordered = append(ordered, occurrence)
+				if occurrences == nil {
+					ordered = append(ordered, occurrence)
+				} else {
+					if ordered == nil {
+						ordered = make([]preparedOccurrence[I], len(occurrences))
+					}
+					ordered[*occurrence.ordinal] = occurrence
+				}
 			}
 		}
 		if enforceRequired && binding.meta.Required && !binding.deferredRequired && !value.supplied && missingRequired == "" {
@@ -313,9 +319,12 @@ func prepareInputWithOccurrences[I any](spec CommandSpec[I], flagValues, flagSpe
 		return preparedInput[I]{}, err
 	}
 	preparedValues := append([]preparedValue[I](nil), preparedFlags...)
-	sort.SliceStable(ordered, func(i, j int) bool { return *ordered[i].ordinal < *ordered[j].ordinal })
+	// Parsed occurrences use dense parser positions; without a parser log the
+	// fallback ordinals were assigned in the same order as the append above.
 	for _, occurrence := range ordered {
-		preparedValues = append(preparedValues, preparedValue[I]{apply: occurrence.apply})
+		if occurrence.apply != nil {
+			preparedValues = append(preparedValues, preparedValue[I]{apply: occurrence.apply})
+		}
 	}
 	for i, argument := range spec.Arguments {
 		binding := argument.binding