Komodo got it from Emacs, its called flymake-mode

see emacs wiki or sourceforge

But be aware of downsides: Vulnerabilities when editing untrusted code... (Komodo)!

searching for "flymake YourEditor" will show you more alternatives.

Cheers Rolf

In reply to Re: On the fly syntax checkers (flymake in emacs) by LanX
in thread On the fly syntax checkers in emacs, ultraedit or vi by ISAI student

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