[bonzini]

The ISPF editor is actually more than decent. About 20 years ago my father was writing COBOL (on both AS/400, now iSeries, and PC) using SPFPC, an MS-DOS editor inspired by ISPF. The line command/primary command mechanism is really no more quirky than vi's movement and insert modes, and it makes a lot of sense for languages like COBOL.

[tolle]

SEU, the built in editor on the iSeries/IBM i, is however rather shitty. It does actually do some linting, but no syntax highlighting and the 5250 interface never really got improved as much as 3270, so its 24x80 or 27x132. Granted you're supposed to use an eclipse based IDE since SEU is no longer supported, but to just look at stuff really quick. A fast editor is preferred.

But I agree, ISPF editor is rather good.

[southern_cross]

I think SEU is far better than you seem to giving it credit for. In fact, I used it for decades and my only real complaints about it started when IBM stopped actively maintaining it. Over the years I also tried using various other "modern" editors, only to eventually cast them aside as being too unstable, buggy, or just slow and clunky (like Eclipse). In fact, I can only recall one particular instance where using such an editor (Eclipse in this case) actually proved unquestionably advantageous over using SEU, but even then I quickly got annoyed at some of the stupid (IMO) implementation details of it.

[chiph]

When Java was first available on the AS/400 (ported by a man at IBM UK - I have forgotten his name), I tried to use SEU as my editor (me being a PC programmer). OMG worst experience ever.