> Pretty sure it was the world's first IDE, not just an IDE.

That probably depends on whether you count live-coding environments like Smalltalk had as “IDEs”

Hmm... you may be right. Here's the Smalltalk environment from 1980, it is pretty impressive: https://www.youtube.com/watch?v=JLPiMl8XUKU

Not only Smalltalk, check Interlisp-D, Mesa XDE and Mesa/Cedar.

Xerox PARC workstations were the first IDEs, alongside Lisp Machines from Genera and TI.

That's pretty much just like a modern window-based user interface... in 1980!! It has overlapping windows, windows can be minimized and moved around, context menu via right-click, spreadsheet-like data... truly amazing.

You can try it here: http://www.cdglabs.org/thinglab/ (Smalltalk-78)

AFAIK the first "IDE" was the one in the original BASIC, or at least the first one to called that. It was command-line based (no fancy GUIs back then) but it allowed editing, debugging and compiling (despite BASIC dialects being commonly interpreted, the original BASIC was a compiler) from the same environment.

BEEP...

BASIC >

I have to admit that I still judge programming tools, and in fact, entire computers, against the beloved BASIC prompt. You flipped a switch, got a BEEP, and 3 seconds later, you were in heaven.

Today the closest thing for me is firing up a PC and opening a Jupyter notebook. But it's certainly not the same.

I remember wondering how on earth you could write Pascal programs without line numbers since that was the difference between running a command and entering/editing a program in the Apple ][ environment. I don't remember if Apple Pascal had what would qualify as an IDE now, although it had its own OS which made it less attractive to me.

> I remember wondering how on earth you could write Pascal programs without line numbers

You use a program called EDLIN that writes the line numbers for you, and even renumbers your lines automatically whenever you have to insert something in the middle of your program. It's really neat!

I did my first text processing exam using edlin, "It's really neat!" isn't something I would use to describe it.

I think I recall UCSD Pascal which had a sort of IDE. There' a video on IMSAI, I sued the Apple version IIRC...

https://www.youtube.com/watch?v=Wv5IKhv4Akw

Possibly the environment described in https://en.wikipedia.org/wiki/The_Mother_of_All_Demos might be the first.

No. It was very similar to the UCSD Pascal system. And as others have stated, Smalltalk beat it by a decade and a half.