NIX_StringMatcher

NIX_StringMatcher is a lookup table for strings. You give it a list of candidate strings and a judge_string to compare against, and it returns the index of the first candidate that matches exactly - or -1 if nothing matches. If you've ever wanted to branch a workflow on "what category did the model just return?", this is the node that turns a string into a number you can switch on.

It's part of the NIX pack, which is a small, dependency-light utility collection (numpy + Pillow, no models). One install gets you this plus the pack's crop, rotate, and save nodes.

How it works

Required inputs: string_1, string_2, and judge_string. An inputcount dial (default 2, up to 32) controls how many candidates participate, and the node dynamically adds string_3 through string_32 inputs to match. The dynamic inputs come from a small web extension that ships with the pack - if you don't see string_3+ on the node, update ComfyUI's frontend or check that the pack's web/ folder is present.

The logic is dead simple:

• Normalize everything to strings (it won't crash on numbers, it just stringifies them).
• Compare judge_string against string_1, then string_2, then string_3, ... in order.
• Return the index (INT) of the first exact match - 1-based, so string_1 → 1.
• No match → -1.

Two details that matter:

• Exact match. Case-sensitive, no substring, no fuzzy, no wildcard. "Cat" does not match "cat".
• First match wins. If two candidates are identical, the lower index wins.

Where it slots in

The classic combo: an LLM or prompt node returns a free-form string, you want to route on it. NIX_StringMatcher turns "the model said landscape" into a clean integer, and that integer feeds straight into NIX_SwitchAnything - index in, the right branch out. Same idea for filenames, model names, or any classification result you need to act on.

The -1 case is the one to design for: a judge string that matches none of your candidates silently falls through. Route it to a default branch rather than assuming it can't happen.

Getting it installed

• ComfyUI Manager: search "NIX" / "NIX ComfyUI Plugin", or Install Custom Nodes → Git URL → https://github.com/J-ChenX/ComfyUI-NIX. Restart after.
• By hand:

  cd ComfyUI/custom_nodes
  git clone https://github.com/J-ChenX/ComfyUI-NIX
  

  Restart ComfyUI. Under the "NIX" category.

Things that will bite you

• Exact, case-sensitive matching. If your judge string has trailing whitespace or a different case, you get -1 and no explanation. Normalize upstream if you can.
• inputcount clamps to 2–32. It silently bounds itself; don't rely on it erroring if you set it out of range.
• The dynamic inputs need the web folder. On a bare install that skips web/, only string_1 and string_2 may be available.
• Quiet pack. Essentially no community footprint for NIX as of mid-2026 - no copied workflows to lean on, but the matching logic is a short readable block if you ever doubt the order it checks in.