struct: changing meaning of obj.[fun ...] syntax.

Until now, the obj.[fun ...] syntax has uselessly denoted
exactly the same thing as [obj.fun ...]. This latter syntax
is what should be used for that meaning.

The new meaning of obj.[fun ...] will be that it performs
method dispatch, where obj is passed to obj.fun as
the leftmost argument: obj.[fun ...] is [obj.fun obj ...],
with obj evaluated once.

* share/txr/stdlib/struct.tl (qref): Expansion change done
here, with backward compat switch.

* share/txr/stdlib/termios.tl (termios (go-raw, go-cbreak)):
Some a.[b c] turned to [a.b c] here.

* tests/012/oop.tl (animal print): Likewise.

* tests/012/struct.tl: Likewise, and some expansion tests
updated to reflect the new expansion.

* txr.1: Documentation revised in multiple places and compat
note added.

2 files changed, 16 insertions, 6 deletions

diff --git a/share/txr/stdlib/struct.tl b/share/txr/stdlib/struct.tl
index 64cd2e76..2eecfbc7 100644
--- a/share/txr/stdlib/struct.tl
+++ b/share/txr/stdlib/struct.tl
@@ -223,11 +223,21 @@
              :))
          (((dw sym . args))
           (if (eq dw 'dwim)
-            ^[(slot ,obj ',(sys:check-slot form sym)) ,*args]
+            (let ((osym (gensym)))
+              (sys:check-slot form sym)
+              ^(slet ((,osym ,obj))
+                 ,(if (and (plusp sys:compat) (<= sys:compat 251))
+                    ^[(slot ,osym ',sym) ,*args]
+                    ^[(slot ,osym ',sym) ,osym ,*args])))
             :))
          (((dw sym . args) . more)
           (if (eq dw 'dwim)
-            ^(qref [(slot ,obj ',(sys:check-slot form sym)) ,*args] ,*more)
+            (let ((osym (gensym)))
+              (sys:check-slot form sym)
+              ^(qref (slet ((,osym ,obj))
+                       ,(if (and (plusp sys:compat) (<= sys:compat 251))
+                          ^[(slot ,osym ',sym) ,*args]
+                          ^[(slot ,osym ',sym) ,osym ,*args])) ,*more))
             :))
          (((sym . args))
           (let ((osym (gensym)))
diff --git a/share/txr/stdlib/termios.tl b/share/txr/stdlib/termios.tl
index 93fcc958..5d2423dc 100644
--- a/share/txr/stdlib/termios.tl
+++ b/share/txr/stdlib/termios.tl
@@ -56,15 +56,15 @@
   (if (boundp 'iexten)
     tio.(clear-lflags iexten))
   tio.(set-cflags cs8)
-  (set tio.[cc vmin] 1)
-  (set tio.[cc vtime] 0))
+  (set [tio.cc vmin] 1)
+  (set [tio.cc vtime] 0))
 
 (defmeth termios go-cbreak (tio)
   tio.(clear-iflags icrnl)
   tio.(clear-lflags icanon)
   tio.(set-lflags isig)
-  (set tio.[cc vmin] 1)
-  (set tio.[cc vtime] 0))
+  (set [tio.cc vmin] 1)
+  (set [tio.cc vtime] 0))
 
 (defmeth termios string-encode (tio)
   (let ((*print-base* 16))