sam: remove s (substitute) command use x (extract) and c (change) instead

They are roughly equivalent, instead of

 s/pattern/replacement/

to replace the first occurrence of pattern you can specify an address
to the change command:

 /pattern/ c/replacement/

the only difference being that the first command is restricted to the
current line.

 -+x/pattern/ c/replacement/

also restrictes matches to the current line, but performs the substitution
on the whole line not only the first match. Currently it is not possible
to only replace the n-th match as `s2/pattern/replacement/` would do
in sam(1).

A possible alternative syntax generalizing this concepts and applying
it to the `x` and `g` commands will be investigated in the future.

Global substitution as in

 %s/pattern/replacement/g

can be performed using

 x/pattern/ c/replacement/

1 files changed, 0 insertions, 6 deletions

diff --git a/man/vis.1 b/man/vis.1
index f9274e1..4cc8dff 100644
--- a/man/vis.1
+++ b/man/vis.1
@@ -452,12 +452,6 @@ the range.
 .It Sy d
 Delete the text in range.
 .\" Set dot.
-.It Sy s/regexp/text/
-Substitute
-.Sy text
-for the first match of the regular expression in the range.
-Currently implemented in terms of
-.Xr sed 1 "."
 .El
 .
 .Ss Display commands