Deep Merge with mergeOverwrite and dict

Sometimes you need to assemble a map inside a template. The dict function creates one from alternating key and value pairs.

You often have chart defaults plus user overrides, and you want a single combined map. That is exactly what a merge produces.

The merge function copies keys from source maps into a destination, but it keeps the destination value whenever a key already exists.

With merge, the first argument wins on any clashing key, so it is ideal when user input should override your defaults.

The mergeOverwrite function does the opposite: later source maps overwrite the destination, layering values on top.

Both helpers merge recursively: nested maps are combined key by key rather than the whole subtree being replaced wholesale.

Careful: merge and mergeOverwrite mutate their first argument in place. Pass a fresh dict if you must keep the original intact.

A common pattern is to start from a defaults dict, then layer user values on top so unset keys fall back safely.

Once merged, you treat the result like any map and pull keys out with dot or the index function as usual.

To emit a merged structure as YAML, pipe it through toYaml and nindent so the block lands at the right indentation.

When a key name is dynamic or holds odd characters, reach into the map with the index function instead of dot access.

Quick check on overwrite direction.

You met dict to build maps, merge to keep destination keys, and mergeOverwrite to let later values win, all merging deeply. 🎉