Is anyone aware of an emacs mode or function that will reformat a buffer holding a delimited file such that each delimiter (e.g. tab) defines a "column" with the width of each column set to the longest entry?
I can reset the tab-width variable but that makes all columns equal width. I would much prefer variable-width columns if possible (like how a spreadsheet program like excel would display such a file after resizing the columns).
Let's assume your delimiter is TAB. Mark the whole buffer, then:
C-u M-x align-regexp \(\s-*\)TAB RET RET RET y
Where TAB in there is an actual tab char. See my similar answer here:
http://stackoverflow.com/questions/970759/how-to-align-arguments-to-functions-in-emacs/971435#971435
Org-mode as suggested by huaiyuan did just what I wanted.
To give an example to others, after I installed org-mode I found the following to work well.
Open a new file in org-mode C-x C-f table.org and then M-x org-table-import to import the delimited file. And your done.
The C-| command didn't work for me to convert pre-existing buffer contents into a table, it just inserted a new table, but I don't know org-mode yet.