Find and replace in diagram code

Search and replace inside diagram source is the fastest way to do the edit people most often do by hand: renaming something that appears in fifteen places.

Column select is the other tool worth knowing, for editing the same position across many lines.

#What this is for

Renaming a node, service or entity throughout a diagram.
Editing the same field across many lines.
Finding where something is defined in a long source.

#How it works

The diagram text editor showing numbered lines of Mermaid flowchart code with several matches highlighted, and a find and replace bar along the bottom. — The bar opens under the code with match case, regular expression and whole word options, and replaces one match or all of them.

Action	How
Find	Ctrl+F opens the search panel.
Replace	Ctrl+H, or the replace field in the search panel.
Replace all	Applies to the whole source at once.
Column select	Hold Alt and drag to select the same columns across lines.
Multi-cursor	Alt+click to place several cursors.

#A few things that catch people out

Replace all is not undone selectively. Check the count before confirming a large replace.
Column select is how you add the same suffix to twenty lines in one gesture.
The preview updates after the replace, so an error is immediately visible.

Diagram code templates

A working starting point per language.

Import diagram source from a file

Bringing in source you already have.

Text editor

Back to the editor overview.

The source is right there. Read it.