Update HISTORY and README.

HISTORY.md

@@ -4,10 +4,8 @@ History of SixtyPical
 0.16
 ----
 
-*   Removed `--prelude` in favour of specifying both format and prelude
-    with a single option, `--output-format`.  Documentation for same.
-*   `or a, z`, `and a, z`, and `eor a, z` compile to zero-page operations
-    if the address of z < 256.
+*   Added `save` block, which allows the named locations to be modified
+    arbitrarily inside the block, and automatically restored at the end.
 *   More thorough tests and justifications written for the case of
     assigning a routine to a vector with a "wider" type.
 *   Support for `copy [ptra]+y, [ptrb]+y` to indirect LDA indirect STA.
@@ -15,6 +13,10 @@ History of SixtyPical
 *   Support for `I a, btable + x` where `I` is `add`, `sub`, `cmp`,
     `and`, `or`, or `xor`
 *   Support for `I btable + x` where `I` is `shl`, `shr`, `inc`, `dec`
+*   `or a, z`, `and a, z`, and `eor a, z` compile to zero-page operations
+    if the address of z < 256.
+*   Removed `--prelude` in favour of specifying both format and prelude
+    with a single option, `--output-format`.  Documentation for same.
 
 0.15
 ----

README.md

@@ -87,28 +87,30 @@ Is that consistent with `st`?  Well, probably it is, but we have to explain it.
 It might make more sense, then, for it to be "part of the operation" instead of "part of
 the reference"; something like `st.hi x, word`; `st.lo y, word`.  Dunno.
 
-### Save values
+### Save multiple values in single block
 
-This preserves them, so that, semantically, they can be used later even though they
-are trashed (or otherwise alternately used) inside the block.
-
-Inside the block, we set them as writeable (but not meaningful).  When the block
-exits, we restore whatever status they had.
-
-This act will trash `a`, both in the block, and outside it, unless the value being
-saved is `a`.  One idiom would be something like
+As a shortcut for the idiom
 
     save a { save var {
         ...
     } }
 
-which would save all values.  Maybe abbreviate this to
+allow
 
     save a, var {
         ...
     }
 
-This can use the stack.  But it need not use the stack.
+### Save values to other-than-the-stack
+
+Allow
+
+    save a to temp_a {
+        ...
+    }
+
+Which uses some other storage location instead of the stack.  A local static
+would be a good candidate for such.
 
 ### Make all symbols forward-referencable