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Show HN: Mermaid ASCII Diagrams (mermaid-ascii.art)
quuxplusone 4 days ago [-]
Some nits:

The "Example" buttons don't jump out at me; I found them but it took a while. Also consider labeling them with their point, e.g. "Example 3: Color"

If you change the input text to something well-formed, the graph seems to update immediately. But if you change it to something ill-formed, the graph doesn't update immediately — and then if you click "Generate" manually, it blanks the input box. Either this is a bug, or the "Generate" button doesn't do what I think it does (i.e. generate output). Again, adding a noun to the verb might help. Or just adding some usage information somewhere on the page.

For those like me who've never heard of "Mermaid," apparently it's like GraphViz's dot language but different. https://github.com/mermaid-js/mermaid I tried the flowchart example from Mermaid's own README, but it didn't come out right: looks like the shape characters [] and {} aren't handled.

lordswork 4 days ago [-]
Counter-nit: I found the examples within a few seconds.
brink 4 days ago [-]
Counter-counter-nit: I did not.
wigster 3 days ago [-]
nor i
dragonsky 2 days ago [-]
I did
AlexanderGrooff 4 days ago [-]
Thanks for the feedback! I agree that the web UI can be improved (quite) a bit, most of my efforts went into the actual generation of the diagrams. I'll have a look at prettifying it.
matt3210 4 days ago [-]
Same, I had no idea there were examples until I read this.
virtualritz 4 days ago [-]
This obviously needs a direct pipe into Svgbob!

https://ivanceras.github.io/svgbob-editor/

smusamashah 3 days ago [-]
everybodyknows 3 days ago [-]
There is another, related class of tools, and that is graphical editors of the Unicode box-drawing characters:

https://github.com/lewish/asciiflow

https://github.com/tbanel/uniline/

Or, less ergonomically, the general rectangle-editing commands built into more powerful code editors e.g. Emacs.

With these, simple but fairly pretty box+line+text diagrams can be inlined with your source code comments. This unification may help in the perennial struggle to keep software architecture and source code reality in sync.

Myrmornis 3 days ago [-]
https://d2lang.com/ is really nice.

Also I used to use https://swimlanes.io/ before d2.

everybodyknows 3 days ago [-]
pkaye 4 days ago [-]
Needs to have a '+' and the elbows and T intersections.
nunobrito 4 days ago [-]
Hey, where are the mermaids?!?

But now seriously.. the diagrams are working really well for simple examples, thank you so much for sharing this tool. I have bookmarked your page, my documentation is based on text files and often have to build these kind of diagrams too.

The example buttons took me a while to be found, but are good for syntax explanation. Thank you for making this available.

AlexanderGrooff 4 days ago [-]
Thanks for the kind words!
jonahx 4 days ago [-]
Nice work, I love ascii diagrams. Especially useful when you want a visual explanation that can be embedded directly in source code.

Small nit on layout: 90 degree joints should use "+" in the connecting lines, as they do in the boxes.

AlexanderGrooff 3 days ago [-]
Thanks for the recommendation. I've added the "+" corners in v0.5.1.
tiagoafpereira 4 days ago [-]
PhilipRoman 3 days ago [-]
I use https://metacpan.org/dist/Graph-Easy/view/bin/graph-easy There is a package perl-graph-easy for it in AUR (it's a command line frontend for the perl library)
zczc 4 days ago [-]
comebhack 3 days ago [-]
I have been using Monodraw for a long time: https://monodraw.helftone.com/

It's a macOS app and I've found it great. However if given an ASCII diagram, you cannot edit it with the same ease as creating a new one (e.g. reflowing text or resizing boxes).

I really like the idea of having the mermaid source and the ASCII diagram together, so you could use the source to change the diagram if needed. But I feel that would feel cluttered to have both in a plain text file or comment, where ASCII diagrams shine.

ithkuil 3 days ago [-]
Is there something that can turn those ascii diagrams back into mermaid sources?

I tried the first example with gpt-o1 and the result wasn't bad:

    graph LR
    A --> B --> D
    A --> C
    B --> C
    D --> C
would a smaller model but fine tuned on many syntetic renderings do a better job?
jcgrillo 3 days ago [-]
It would be pretty cool to be able to draw a flowchart or graph on a tablet and have it automatically turned into mermaid source. That's exceptional compression.
ithkuil 2 days ago [-]
For me it's more about the ability of modifying the diagram in a predictable way
girvo 4 days ago [-]
Hah we rely on Mermaid a _heap_ at work for building internal dependency graphs from `yarn info` JSON data and a super lazy depth-first graph haha. Super useful, nice to see another renderer!

ts-directed-graph outputs Mermaid :)

This tool seems way more useful for hand-made ones, definitely bookmarking

danpalmer 4 days ago [-]
Out of interest have you managed to get Mermaid graphs rendering outside of a browser?

I was trying to do this a while back so I could do server side rendering of graphs, but it seemed to depend strongly on the presence of a DOM. Couldn’t quite get it working with JS-DOM either.

pjungwir 3 days ago [-]
I've used [mmdc](https://github.com/mermaid-js/mermaid-cli) to generate mermaid images from a Makefile. It looks like it is implemented with puppeteer, so perhaps it doesn't quite fit your request. But if you just want something you can use at the cli, it is great.
danpalmer 3 days ago [-]
Thanks. You're right, unfortunately this doesn't fit my needs, but I can see how it would be fine for CLI and casual use cases.
piedpiper99 4 days ago [-]
I supposed it's good for basic usage. I just tried a more complex graph and it didn't render well.
the_arun 4 days ago [-]
I use this for generating AWS deployment diagrams, which is kinda similar - https://github.com/mingrammer/diagrams
Lorak_ 3 days ago [-]
Are you planning to support more of mermaids features? I tried one example where this could be useful to me - Mermaids gitGraph - and it looks like it's not supported.
AlexanderGrooff 3 days ago [-]
Yes, over the course of time I want to increase the coverage of the Mermaid syntax.

PS: it's open source so feel free to help out ;) https://github.com/AlexanderGrooff/mermaid-ascii

abraxas 4 days ago [-]
In the age of AI someone automated Mentifex[1]!

[1] https://nothingisreal.com/mentifex_faq.html

prmoustache 3 days ago [-]
graph TD

project is called Mermaid ASCII -->|expectation| It supports mermaidjs syntax

It supports mermaidjs syntax -->|I tried| It doesn't

It doesn't -->|conclusion| I am a bit bummed

https://mermaid.js.org/syntax/examples.html

AlexanderGrooff 3 days ago [-]
The example you post works just fine ;)

On a serious note, yes not all syntax noted in the Mermaid docs work yet. I'm planning on adding more coverage of the Mermaid syntax over time. For now the basics work and (hopefully) shows its potential.

prmoustache 3 days ago [-]
Yeah, first try I copy pasted the pie charts example wondering how it would render in ascii and was noooo
flykespice 4 days ago [-]
Wow! this will come pretty in hand when building plaintext documentation using diagrams.
nlake906 4 days ago [-]
love it, will definitely be using it for sketching documentation in comments for SQL sprocs, etc.

One request: support for self-reference, i.e. "A --> A", "A --> A & B"

AlexanderGrooff 4 days ago [-]
Thanks, that's a good suggestion. I'm also noticing that's not working as intended.
AlexanderGrooff 4 days ago [-]
Fixed in 0.5.0. Give it a try!
ewalk153 4 days ago [-]
This would be great to build into project readme workflows.
kitd 4 days ago [-]
You can already use Mermaid in GitHub markdown:

https://docs.github.com/en/get-started/writing-on-github/wor...

mcraiha 4 days ago [-]
edflsafoiewq 4 days ago [-]
I don't like that it renders controls on top of the diagram.
4 days ago [-]
octopusRex 4 days ago [-]
I'm disappointed. I was actually expecting lovely ascii art pictures of mermaids.
derfnugget 4 days ago [-]
Same. This is more than a nit. It's pretty much a need.
kleiba 4 days ago [-]
m4tthumphrey 4 days ago [-]
[flagged]
airstrike 4 days ago [-]
[flagged]
4 days ago [-]
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