public <T> void addValueFlag(
            final @NonNull CommandFlag<T> flag,
            final @NonNull T value
    ) {
        ((List<T>) this.flagValues.computeIfAbsent(
                flag.name(),
                $ -> new ArrayList<>()
        )).add(value);
    }
Store a value associated with a value flag

@param flag  Value flag
@param value Flag value
@param <T>   Value type
cloud-core/src/main/java/org/incendo/cloud/parser/flag/FlagContext.java