Greetings all! Continuing to share little tips & tricks. here is one for 'tbl'.
Normnally, if you want a table with vertical rules on either side, you will enter a format line like |l c r|. This will have the effect that between the left-hand vertical rule "|" and the first character of the first field there will be a space (of width 1n), and similarly between the last character of the last field and the right-hand vertical rule "|". However, you may (for good reasons ... that's a matter for your taste in such things) wish to have no such spaces, either at both side, or just at one side. This could arise, for instance, if a graphical object has been defined as a ".char" and you wish this to abut on the vertical rule. There is no 'tbl' option which allows a "no space" to be set in this context. However, there is a trick. This is to use dummy columns at the left and/or right, with associated sero column spacings. Here is a simple example. First, some text with abutting vertical rules left & right is set using only troff commands, to provide a reference object for the performance of 'tbl' in the subsequent lines. Then a 2-line table which shows the desired effect is set. .br \Z'\D'l 0 0.45i''\v'1m'and three words\v'-1m'\D'l 0 0.45i' .sp 2 .TS tab(#); r0|c0|l. #two words# #and three words# .TE .\"## and compare with .sp .TS tab(#); |c|. two words and three words .TE Thus the equivalent troff-generated and tbl-generated outputs are exactly aligned. This works because 'tbl' only pads with extra space on either side if the "| ... |" are present; otherwise, the left-hand extent of the table contents is flush left, and similarly for the right-hand extent. Since the dummy columns are associated with zero-space separation from their neighbours, and have no content, they will have width 0, and thwe vertical rules will be flush left/right. Comments welcome! Best wishes to all, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@wlandres.net> Fax-to-email: +44 (0)870 094 0861 Date: 05-Jul-11 Time: 16:56:44 ------------------------------ XFMail ------------------------------
