Move identifier-syntax to (chibi ast)

lib/chibi/ast.scm

@@ -109,6 +109,34 @@
        ((opcode? x) (cond ((opcode-name x) => string->symbol) (else x)))
        (else x)))))
 
+;;> \section{Identifier Macros}
+
+;;> \procedure{(make-variable-transformer proc)}
+
+;;> Returns a new procedure wrapping the input procedure \var{proc}.
+;;> The returned procedure, if used as a macro transformer procedure,
+;;> can expand an instance of \scheme{set!} with its keyword on the
+;;> left hand side.
+
+;;> \macro{(identifier-syntax clauses ...)}
+
+;;> A high-level form for creating identifier macros. See
+;;> \hyperlink["http://www.r6rs.org/final/html/r6rs/r6rs-Z-H-14.html#node_idx_796"]{the R6RS specification.}
+
+(define-syntax identifier-syntax
+  (syntax-rules (set!)
+    ((_ template)
+     (syntax-rules ()
+       ((_ xs (... ...))
+        (template xs (... ...)))
+       (x template)))
+    ((_ (id_1 template_1) ((set! id_2 pattern) template_2))
+     (make-variable-transformer
+      (syntax-rules (set!)
+        ((set! id_2 pattern) template_2)
+        ((id_1 xs (... ...)) (template_1 xs (... ...)))
+        (id_1 template_1))))))
+
 ;;> \section{Types}
 
 ;;> All objects have an associated type, and types may have parent

lib/chibi/ast.sld

@@ -1,7 +1,8 @@
 
 (define-library (chibi ast)
   (export
-   analyze optimize env-cell ast->sexp macroexpand type-of
+   analyze optimize env-cell ast->sexp macroexpand identifier-syntax
+   type-of
    Object Input-Port Output-Port Opcode Procedure Bytecode Macro Env
    Number Bignum Flonum Integer Complex Char Boolean
    Symbol String Byte-Vector Vector Pair File-Descriptor

tests/syntax-tests.scm

@@ -84,11 +84,11 @@
  ;; this could be fixed in theory)
  (modules
   (test-begin "identifier syntax")
-  (define syntax-test-env (environment '(chibi)))
+  (define syntax-test-env (environment '(chibi) '(chibi ast)))
 
   (eval
    '(define-syntax low-level-id-macro
-      (er-macro-transformer*
+      (er-macro-transformer
        (lambda (expr rename compare)
          (if (pair? expr)
              (list (rename 'quote) 'operator)
@@ -102,7 +102,7 @@
   (eval
    '(define-syntax low-level-vt
     (make-variable-transformer
-     (er-macro-transformer*
+     (er-macro-transformer
       (lambda (expr rename compare)
         (list (rename 'quote)
               (if (pair? expr)