support +line[,column] and filename:line:column syntaxes when opening files

* This is done via the new opener.tes in the standard library.
* Some programs that use $EDITOR expect the +line syntax to work.
* You can copy filename:line:column directly from GCC error messages
  and filename:line from grep output.
* Since there may be safe file names beginning with "+" or containing colons,
  there needs to be a way to turn this off, especially for scripts that don't
  know anything about the filenames to open.
  This is done with "--".
  Unfortunately, the first "--", that stops parameter processing,
  is always removed from the command line and not passed down into TECO land.
  This is not a problem for stand-alone scripts,
  since the script filename is already stopping option processing, so "--"
  would get passed down.
  But when calling the profile via `sciteco -- ...`, you could prevent leading
  minus signs to cause problems but since the `--` is removed, opener.tes cannot
  use it as a hint.
  Therefore, we introduced `-S` as a new alternative to `--`, that's always passed
  down as `--` (i.e. it is equivalent to "-- --").
  In other words, `sciteco -S *` will always open exactly the specified files
  without any danger of misinterpreting certain file names.
  Should we ever switch to a custom option parsing algorithm, we might preserve
  "--" (unless after --mung) and thus get rid of "-S".
* This advanced behavior can be tweaked by the user relatively easily.
  In the easiest case, we could replace M[opener] with
  <:L;R 0X.f [* @EB/^EN.f/ ]* L>
  in ~/.teco_ini to completely disable the special syntax.

2 files changed, 39 insertions, 2 deletions

diff --git a/lib/Makefile.am b/lib/Makefile.am
index 8bf80be..70f39b7 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -1,6 +1,6 @@
 
-dist_scitecolib_DATA = color.tes lexer.tes session.tes fnkeys.tes
-dist_scitecolib_DATA += string.tes getopt.tes
+dist_scitecolib_DATA = color.tes lexer.tes session.tes opener.tes \
+                       fnkeys.tes string.tes getopt.tes
 
 # Helper script for creating lexer definitions
 EXTRA_DIST = scite2co.lua
diff --git a/lib/opener.tes b/lib/opener.tes
new file mode 100644
index 0000000..6a57317
--- /dev/null
+++ b/lib/opener.tes
@@ -0,0 +1,37 @@
+!*$
+ * M[opener] -- Open a number of files from the current buffer
+ *
+ * This is usually the unnamed buffer as initialized from the command line.
+ * It supports both the +line[,column] and filename:line[:column] syntaxes.
+ * Since this may make it hard to open files with certain file names, all
+ * filenames after "--" are interpreted verbatim.
+ *!
+@[opener]{
+  <.-Z;
+    !* --/-S stops processing of special arguments *!
+    0A--"= 1A--"= 2A-10"=
+      L <:L;R 0X.f [* EBN.f ]* L> 1;
+    '''
+
+    1U.l 1U.c
+    !* +line[,column] *!
+    0A-+"=
+      C 0A"D \U.l W 0A-,"= C \U.c ' 0A-10"=L' '
+    '
+
+    !* filename:line[:column][:] *!
+    LR -A-:"=R' <-A"DR|1;'> -A-:"=
+      \U.a R <-A"DR|1;'> -A-:"=
+        \U.l Q.aU.c R
+      |
+        Q.aU.l 1U.c
+      '
+    |
+      LR
+    '
+
+    0X.f [*
+      EBN.f Q.c-1,Q.l-1ESFINDCOLUMN:J
+    ]*
+  L>
+}