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--- ch2_1_backquote [2021/04/18 03:25] – created admin
+++ ch2_1_backquote [2022/02/23 05:54] (current) – admin
@@ Line 8: / Line 8: @@
 </code>
-But in backqouted list, some parts can be switched back to evaluation with comma character (see unquote):
+But in backquoted list, some parts can be switched back to evaluation with comma character (see ''UNQUOTE''):
 <code lisp>
@@ Line 19: / Line 19: @@
 <code lisp>
 >'(a ,(+ 1 2) c)         ; quoted list
-(A (UNQUOTE (+ 1 2)) C)  ; form (+ 1 2) evaluated
+(A (UNQUOTE (+ 1 2)) C)  ; comma character expanded, but not evaluated
 </code>
-Quote form expects one argument, which is not evaluated, but switched to data and returned as is. For convenience we can use special character '' '%%%%'' for quoting, which is expanded to quote form automatically by the //reader//:
+And multiple backqoutes are ignored:
 <code lisp>
-'(a b c)         ; these expressions ..
+>``(a ,(+ 1 2) c)   ; multiple backquoting ..
-(quote (a b c))  ; .. are the same
+(A 3 C)             ; .. behaves as single backquote
 </code>
+The forms ''BACKQUOTE'', ''UNQUOTE'' and ''SPLICE-UNQUOTE'' are useful for writing macros.