> > this is one thing that byron understood in his version of rc.
> > he had
> > x=``ifs {cmd}
> > the `` was required since `singleton was allowed in his version.
> > i think that one could just extend the grammar to allow
> > x=`ifs {cmd}
> > and i think it would be even better if it were
> > x=`splitchars {cmd}
> > so ifs is never set.
>
> I don't quite understand the first two examples. Do they set ifs only
> within the {} ? I guess that risks breaking any scripts you might want
> to run as cmd, so yeah, the 3rd looks good.
i implemented the 3d this evening in a compatable way with
Traditional Rc. there's an argument that it's not completely
necessary, but it's so easy to make a mistake and type this
ifs=$something x=`{something}
leaving ifs set rather than the intended
ifs=$something {x=`{something}}
i also don't see a argument against making the splitting string
local to the backq. i don't believe i've ever written a script that
uses the fact that ifs can be set once and reused with it's nonstandard
value.
- erik
----
; 8.out
broken! x=`{echo a b c d}
broken! whatis x
x=(a b c d)
broken! x=`/$nl {pwd}
broken! whatis x
x=(usr quanstro src rc)
broken! ifs=/$nl {x=`{pwd}}
broken! whatis x
x=(usr quanstro src rc)
broken! diffy -c *.[chy]
diff -c /n/dump/2011/0429/usr/quanstro/src/rc/code.c code.c
/n/dump/2011/0429/usr/quanstro/src/rc/code.c:145,158 - code.c:145,167
emitf(Xconc);
break;
case '`':
+ emitf(Xmark);
+ if(c0==0){
+ emitf(Xword);
+ emits(strdup("ifs"));
+ emitf(Xdol);
+ }else{
+ outcode(c0, 0, brkaddr);
+ emitf(Xglob);
+ }
emitf(Xbackq);
if(havefork){
p = emiti(0);
- outcode(c0, 0, brkaddr);
+ outcode(c1, 0, brkaddr);
emitf(Xexit);
stuffdot(p);
} else
- emits(fnstr(c0));
+ emits(fnstr(c1));
break;
case ANDAND:
outcode(c0, 0, brkaddr);
diff -c /n/dump/2011/0429/usr/quanstro/src/rc/havefork.c havefork.c
/n/dump/2011/0429/usr/quanstro/src/rc/havefork.c:83,93 - havefork.c:83,92
int pfd[2];
char *s, *wd, *ewd, *stop;
struct io *f;
- var *ifs = vlook("ifs");
word *v, *nextv;
Rune r;
- stop = ifs->val? ifs->val->word: "";
+ stop = runq->argv->words->word;
if(pipe(pfd)<0){
Xerror("can't make pipe");
return;
/n/dump/2011/0429/usr/quanstro/src/rc/havefork.c:140,145 - havefork.c:139,145
efree(wd);
closeio(f);
Waitfor(pid, 0);
+ popword(); /* ditch split in "stop" */
/* v points to reversed arglist -- reverse it onto argv */
while(v){
nextv = v->next;
/n/dump/2011/0429/usr/quanstro/src/rc/pcmd.c:32,38 - pcmd.c:32,38
break;
case '^': pfmt(f, "%t^%t", c0, c1);
break;
- case '`': pfmt(f, "`%t", c0);
+ case '`': pfmt(f, "`%t%t", c0, c1);
break;
case ANDAND: pfmt(f, "%t && %t", c0, c1);
break;
diff -c /n/dump/2011/0429/usr/quanstro/src/rc/syn.y syn.y
/n/dump/2011/0429/usr/quanstro/src/rc/syn.y:96,102 - syn.y:96,103
| '"' word {$$=tree1('"', $2);}
| COUNT word {$$=tree1(COUNT, $2);}
| WORD
- | '`' brace {$$=tree1('`', $2);}
+ | '`' brace {$$=tree2('`', nil, $2);}
+ | '`' word brace {$$=tree2('`', $2, $3);}
| '(' wordsnl nl ')' {$$=tree1(PAREN, $2);}
| REDIR brace {$$=mung1($1, $2); $$->type=PIPEFD;}
keyword: FOR|IN|WHILE|IF|NOT|TWIDDLE|BANG|SUBSHELL|SWITCH|FN|BREAK
