mirror/guile
mirror/guile
1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-05-03 13:20:26 +02:00
Code Activity

Add news on :select' and :renamer' facilities.

Browse source
This commit is contained in:
Thien-Thi Nguyen 2001-08-25 19:55:56 +00:00
parent 06833fa252
commit b51d7c353c
1 changed files with 55 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

55
NEWS
View file

@ -389,6 +389,61 @@ want to re-export bindings, use the new `re-export' in place of
`export'. The new `re-export' will not make copies of variables when
rexporting them, as `export' did wrongly.
** Module system now allows selection and renaming of imported bindings
Previously, when using `use-modules' or the `#:use-module' clause in
the `define-module' form, all the bindings (association of symbols to
values) for imported modules were added to the "current module" on an
as-is basis. This has been changed to allow finer control through two
new facilities: selection and renaming.
You can now select which of the imported module's bindings are to be
visible in the current module by using the `:select' clause. This
clause also can be used to rename individual bindings. For example:
;; import all bindings no questions asked
(use-modules (ice-9 common-list))
;; import four bindings, renaming two of them;
;; the current module sees: every some zonk-y zonk-n
(use-modules ((ice-9 common-list)
:select (every some
(remove-if . zonk-y)
(remove-if-not . zonk-n))))
You can also programmatically rename all selected bindings using the
`:renamer' clause, which specifies a proc that takes a symbol and
returns another symbol. Because it is common practice to use a prefix,
we now provide the convenience procedure `symbol-prefix-proc'. For
example:
;; import four bindings, renaming two of them specifically,
;; and all four w/ prefix "CL:";
;; the current module sees: CL:every CL:some CL:zonk-y CL:zonk-n
(use-modules ((ice-9 common-list)
:select (every some
(remove-if . zonk-y)
(remove-if-not . zonk-n))
:renamer (symbol-prefix-proc 'CL:)))
;; import four bindings, renaming two of them specifically,
;; and all four by upcasing.
;; the current module sees: EVERY SOME ZONK-Y ZONK-N
(define (upcase-symbol sym)
(string->symbol (string-upcase (symbol->string sym))))
(use-modules ((ice-9 common-list)
:select (every some
(remove-if . zonk-y)
(remove-if-not . zonk-n))
:renamer upcase-symbol))
Note that programmatic renaming is done *after* individual renaming.
Also, the above examples show `use-modules', but the same facilities are
available for the `#:use-module' clause of `define-module'.
See manual for more info.
** The semantics of guardians have changed.
The changes are for the most part compatible. An important criterion