Template:Category/Guide/ slug

Tiny helper: takes a page name as positional arg 1 and returns a mermaid-safe slug by replacing spaces, slashes, and colons with underscores (chained #replace).

Why this lives as its own template: Mermaid IDs can't contain spaces, slashes, or colons. The natural way to write the slugification inline inside Template:Category/Guide/edge's #arraymap formula is a triple-nested #replace — but nested ParserFunctions don't reliably evaluate inside #arraymap's formula or value (they get treated as literal text and the inner pipes get split by the array delimiter, leaving raw {{#replace:...}} markers in the output). Pushing the chain into a sub-template invocation sidesteps this: {{#replace:{{#replace:{{#replace:...|:|_}}|/|_}}| |_}} is a template call, which does evaluate per-iteration inside #arraymap's formula.

Underscore-prefix on the name signals this is an internal helper for the Category/Guide rendering pipeline, not something other templates should call directly.