teskridg@nmsu.edu (Tom Eskridge) (02/12/91)
I came across a piece of code which uses the ~V directive to pass an arguement to the ~T (tab) directive in a format statement. So (format nil "~VThello" 3) => " hello" it also seems to work with other ~ directives too, such as ~A. So, (format nil "~VA" 10 'hello) => "hello " the ~V is not documented in either CLtL I or II. Does anyone have any info on this? tom eskridge computing research laboratory, new mexico state university teskridg@nmsu.edu (505) 646-6247 -- tom eskridge computing research laboratory, new mexico state university teskridg@nmsu.edu (505) 646-6247
mincy@think.com (Jeffrey Mincy) (02/12/91)
In article <TESKRIDG.91Feb11120557@illyria.nmsu.edu> teskridg@nmsu.edu (Tom Eskridge) writes: >the ~V is not documented in either CLtL I or II. Does anyone have any info on >this? >tom eskridge there is no ~V, however, V may be used as a prefix parameter. p386 CLtL: the V prefix parameter takes an argument from arguments as a parameter to the directive. ... This feature allows variable-width fields and the like. If you were so disposed, you could use ~V,V,V,VA -- -- jeff seismo!godot.think.com!mincy
mark@cambridge.apple.com (Mark Preece) (02/12/91)
In article <TESKRIDG.91Feb11120557@illyria.nmsu.edu> teskridg@nmsu.edu (Tom Eskridge) writes: > >I came across a piece of code which uses the ~V directive to pass an >arguement to the ~T (tab) directive in a format statement. So > (format nil "~VThello" 3) => " hello" [stuff deleted] > >the ~V is not documented in either CLtL I or II. Does anyone have any info on >this? > Actually, it is documented in CLTL/II (but - like a certain amount of the format stuff - really hard to find). On page 582: In place of a prefix parameter to a directive, you can put the letter V (or v), which takes an argument from _arguments_ for use as a parameter to the directive. Normally this should be an integer or character object, as appropriate. This feature allows variable-width fields and the like. If the argument used by a V parameter is nil, the effect is as if the parameter had been omitted. It's not the ~V command (the "~" doesn't belong to the V, but to the command it modifies). - Mark.