On 8/31/14, 12:20 AM, lolilolicon wrote:
> Assignment to a subscripted array variable behaves differently for
> nameref vs `printf -v`, as shown below.
[...]
> Is subscripted array variable allowed as argument to `declare -p` in bash?
> A quick test seems to suggest it's not -- consistent with the `printf
> -v` behavior.
>
> Is there a legitimate explanation for this?
It's a bug that results in `arr[0]' being created as a shell variable.
I've attached a patch for people who want to experiment with it.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/
*** ../bash-4.3-patched/subst.h 2014-01-11 21:02:27.000000000 -0500
--- subst.h 2014-09-01 12:16:56.000000000 -0400
***************
*** 48,51 ****
--- 48,52 ----
#define ASS_MKGLOBAL 0x0008 /* force global assignment */
#define ASS_NAMEREF 0x0010 /* assigning to nameref variable */
+ #define ASS_FROMREF 0x0020 /* assigning from value of nameref variable */
/* Flags for the string extraction functions. */
*** ../bash-4.3-patched/variables.c 2014-05-15 08:26:50.000000000 -0400
--- variables.c 2014-09-01 14:37:44.000000000 -0400
***************
*** 2504,2511 ****
int hflags, aflags;
{
! char *newval;
SHELL_VAR *entry;
entry = (hflags & HASH_NOSRCH) ? (SHELL_VAR *)NULL : hash_lookup (name, table);
/* Follow the nameref chain here if this is the global variables table */
if (entry && nameref_p (entry) && (invisible_p (entry) == 0) && table == global_variables->table)
--- 2566,2590 ----
int hflags, aflags;
{
! char *newname, *newval;
SHELL_VAR *entry;
+ #if defined (ARRAY_VARS)
+ arrayind_t ind;
+ char *subp;
+ int sublen;
+ #endif
+ newname = 0;
+ #if defined (ARRAY_VARS)
+ if ((aflags & ASS_FROMREF) && (hflags & HASH_NOSRCH) == 0 && valid_array_reference (name))
+ {
+ newname = array_variable_name (name, &subp, &sublen);
+ if (newname == 0)
+ return (SHELL_VAR *)NULL; /* XXX */
+ entry = hash_lookup (newname, table);
+ }
+ else
+ #endif
entry = (hflags & HASH_NOSRCH) ? (SHELL_VAR *)NULL : hash_lookup (name, table);
+
/* Follow the nameref chain here if this is the global variables table */
if (entry && nameref_p (entry) && (invisible_p (entry) == 0) && table == global_variables->table)
***************
*** 2538,2541 ****
--- 2617,2630 ----
}
}
+ #if defined (ARRAY_VARS)
+ else if (entry == 0 && newname)
+ {
+ entry = make_new_array_variable (newname, table); /* indexed array by default */
+ if (entry == 0)
+ return entry;
+ ind = array_expand_index (name, subp, sublen);
+ bind_array_element (entry, ind, value, aflags);
+ }
+ #endif
else if (entry == 0)
{
***************
*** 2658,2662 ****
if (nameref_cell (nv) == 0)
return (bind_variable_internal (nv->name, value, nvc->table, 0, flags));
! return (bind_variable_internal (nameref_cell (nv), value, nvc->table, 0, flags));
}
else
--- 2747,2752 ----
if (nameref_cell (nv) == 0)
return (bind_variable_internal (nv->name, value, nvc->table, 0, flags));
! /* XXX - bug here with ref=array[index] */
! return (bind_variable_internal (nameref_cell (nv), value, nvc->table, 0, flags|ASS_FROMREF));
}
else
