Re: [PATCH 1/4] getargs: add support for --flags/-f

[Théophile Ranquet]

2012/12/4 Akim Demaille <address@hidden>:
>> +int flag_flag = flag_none;
>
> Well, at least I can say that I am not fond on this name.
> I prefer feature_flag.  So I guess we're heading to --feature.

I have followed this suggestion. Note that a plural, --features, may
have also been appropriate, but I chose to stick to a singular.

> Do we really want to support -f without argument?  That would
> mean "all" IIUC?  Why not actually.

Yes, this is supported and that is indeed the meaning. Since this uses
our regular getargs interface, we also support
--feature=feat1,no-feat2,feat3 and such. However, this is pretty
useless at the moment, so it has not been documented (for this option)
yet.


The changes have been installed into maint as follows (the commit
message was installed like this, with the old "flag" instead of
"feature", but this has been subsequently fixed by using the
build-aux/git-log-fix file):


commit 0db2648930e3b6c376a539aabe368aade83ee29a
Author: Theophile Ranquet <address@hidden>
Date:   Fri Nov 30 14:33:05 2012 +0100

    getargs: add support for --flags/-f

    Introduce -fdiagnostics-show-caret

    * src/getargs.c (flag_flag): New global.
    * src/getargs.h (flag): New enum.

diff --git a/src/getargs.c b/src/getargs.c
index c480649..1b7c6f1 100644
--- a/src/getargs.c
+++ b/src/getargs.c
@@ -63,6 +63,7 @@ bool error_verbose = false;
 bool nondeterministic_parser = false;
 bool glr_parser = false;

+int feature_flag = feature_none;
 int report_flag = report_none;
 int trace_flag = trace_none;
 int warnings_flag = warnings_conflicts_sr | warnings_conflicts_rr
@@ -257,6 +258,26 @@ static const int warnings_types[] =

 ARGMATCH_VERIFY (warnings_args, warnings_types);

+/*-----------------------.
+| --feature's handling.  |
+`-----------------------*/
+
+static const char * const feature_args[] =
+{
+  "none",
+  "caret", "diagnostics-show-caret",
+  "all",
+  0
+};
+
+static const int feature_types[] =
+{
+  feature_none,
+  feature_caret, feature_caret,
+  feature_all
+};
+
+ARGMATCH_VERIFY (feature_args, feature_types);

/*-------------------------------------------.
 | Display the help message and exit STATUS.  |
@@ -301,6 +322,7 @@ Operation modes:\n\
       --print-datadir        output directory containing skeletons and XSLT\n\
   -y, --yacc                 emulate POSIX Yacc\n\
   -W, --warnings[=CATEGORY]  report the warnings falling in CATEGORY\n\
+  -f, --feature[=FEATURE]    activate miscellaneous features\n\
 \n\
 "), stdout);

@@ -316,8 +338,8 @@ Parser:\n\
                                    deprecated by '-Dapi.prefix=PREFIX'\n\
   -l, --no-lines                   don't generate '#line' directives\n\
   -k, --token-table                include a table of token names\n\
-\n\
 "), stdout);
+      putc ('\n', stdout);

       /* Keep -d and --defines separate so that ../build-aux/cross-options.pl
        * won't assume that -d also takes an argument.  */
@@ -333,8 +355,8 @@ Output:\n\
   -g, --graph[=FILE]         also output a graph of the automaton\n\
   -x, --xml[=FILE]           also output an XML report of the automaton\n\
                              (the XML schema is experimental)\n\
-\n\
 "), stdout);
+      putc ('\n', stdout);

       fputs (_("\
 Warning categories include:\n\
@@ -360,6 +382,14 @@ THINGS is a list of comma separated words that
can include:\n\
   `all'          include all the above information\n\
   `none'         disable the report\n\
 "), stdout);
+      putc ('\n', stdout);
+
+      fputs (_("\
+FEATURE is a list of comma separated words that can include:\n\
+  `caret'        show errors with carets\n\
+  `all'          all of the above\n\
+  `none'         disable all of the above\n\
+  "), stdout);

       putc ('\n', stdout);
       printf (_("Report bugs to <%s>.\n"), PACKAGE_BUGREPORT);
@@ -469,6 +499,7 @@ static char const short_options[] =
   "W::"
   "b:"
   "d"
+  "f::"
   "e"
   "g::"
   "h"
@@ -521,6 +552,7 @@ static struct option const long_options[] =

   /* Output.  */
   { "defines",     optional_argument,   0,   'd' },
+  { "flag",        optional_argument,   0,   'f' },

   /* Operation modes.  */
   { "fixed-output-files", no_argument,  0,   'y' },
@@ -613,6 +645,10 @@ getargs (int argc, char *argv[])
        version ();
        exit (EXIT_SUCCESS);

+      case 'f':
+        FLAGS_ARGMATCH (flag, optarg);
+        break;
+
       case 'W':
        FLAGS_ARGMATCH (warnings, optarg);
        break;
diff --git a/src/getargs.h b/src/getargs.h
index ef97822..b2126fc 100644
--- a/src/getargs.h
+++ b/src/getargs.h
@@ -130,6 +130,18 @@ enum warnings
 /** What warnings are issued.  */
 extern int warnings_flag;

+/*-------------.
+| --features.  |
+`-------------*/
+
+enum feature
+  {
+    feature_none  = 0,         /**< No additional feature.  */
+    feature_caret = 1 << 0,    /**< Enhance the output of errors with
carets.  */
+    feature_all   = ~0         /**< All above features.  */
+  };
+/** What additional features to use.  */
+extern int feature_flag;

 /** Process the command line arguments.
  *