nits

beautiful-racket-demo/algebra-demo/main.rkt

@@ -18,7 +18,7 @@
 (define-macro top #'begin)
 
 (define-macro (func-def VAR VARS EXPR)
-  #'(define VAR (λ VARS EXPR)))
+  #'(define (VAR . VARS) EXPR))
 
 (define-macro-cases expr
   [(_ LEFT "+" RIGHT) #'(+ LEFT RIGHT)]

beautiful-racket-demo/precalc-demo/grammar.rkt

@@ -1,11 +1,11 @@
 #lang brag
 
-top : (func-def | expr)*
+top : (func-def | func-app)*
 func-def : /"fun" var /"(" vars /")" /"=" expr
-/vars : [var [/"," var]*]
+/vars : [var (/"," var)*]
 @expr : sum
 sum : [sum ("+" | "-")] product
 product : [product ("*" | "/")] value
 @value : var | INT | func-app | /"(" expr /")"
-func-app : var /"(" [value [/"," value]*] /")"
+func-app : var /"(" [expr (/"," expr)*] /")"
 @var : ID

beautiful-racket-demo/precalc-demo/main.rkt

@@ -18,8 +18,8 @@
 
 (define-macro top #'begin)
 
-(define-macro (func-def ID ARGIDS EXPR)
+(define-macro (func-def VAR VARS EXPR)
-  #'(define ID (λ ARGIDS EXPR)))
+  #'(define (VAR . VARS) EXPR))
 
 (define-macro-cases sum
   [(_ LEFT "+" RIGHT) #'(+ LEFT RIGHT)]

beautiful-racket-demo/precalc-demo/test.rkt

@@ -9,8 +9,7 @@ h() // also 300
 
 fun k(x) = x / 10 / 10 / (x / x)
 k(h()) // 3
-
+k(10 * (15 + 3 * 5)) // 3
-36/6/2 // 3
 
 /*
 multiline comment

beautiful-racket-demo/pythonesque-demo/grammar.rkt

@@ -1,19 +1,15 @@
 #lang brag
 
 top : @statement*
-statement : assignment | func-def | expr | return | for | if | print
+statement : func-def | expr | return | if
-assignment : ID /"=" expr
+func-def : /"def" var /"(" ids /")" /":" @block
+/ids : [var (/"," var)*]
+block : /INDENT @statement* /DEDENT
 @expr : comparison
-comparison : [comparison ("<" | ">")] sum
+comparison : [comparison "<"] value
-sum : [sum ("+" | "-")] product
+@value : var | INTEGER | func-app | STRING
-product : [product ("*" | "/")] value
+func-app : var /"(" @exprs /")"
-@value : ID | INTEGER | func-app | STRING
-func-app : ID /"(" @exprs /")"
 exprs : [expr (/"," expr)*]
-func-def : /"def" ID /"(" ids /")" /":" @block
-/ids : [ID (/"," ID)*]
-block : /INDENT @statement* /DEDENT
 return : /"return" expr
-for : /"for" ID /"in" expr /":" @block
 if : /"if" expr /":" block [/"else" /":" block]
-print : /"print" expr
+@var : ID

beautiful-racket-demo/pythonesque-demo/main.rkt

@@ -1,15 +1,12 @@
 #lang br/quicklang
-(require "grammar.rkt" brag/support racket/pretty racket/stxparam)
+(require "grammar.rkt" brag/support racket/stxparam)
-(provide (except-out (all-from-out br/quicklang) for if print) (all-defined-out) pretty-print)
+(provide #%module-begin (all-defined-out))
 
 (module+ reader
   (provide read-syntax))
 
 (define-lex-abbrev reserved-terms
-  (:or "=" "def" "(" ")" ":" ","
+  (:or "def" "(" ")" ":" "," "return" "<" "if" "else"))
-       "return" "for" "in"
-       "+" "-" "*" "/" "<" ">" "\""
-       "if" "else" "print"))
 (define-lex-abbrev indent (:: (:+ "\n") (:* " ")))
 
 (define prev-indent 0)
@@ -39,7 +36,7 @@
         (set! prev-indent this-indent)
         tok)]
      [(:+ whitespace) (token lexeme #:skip? #t)]
-     [reserved-terms (token lexeme (string->symbol lexeme))]
+     [reserved-terms lexeme]
      [(:+ (:- (:or alphabetic punctuation) reserved-terms))
       (token 'ID (string->symbol lexeme))]
      [(:+ (char-set "0123456789"))
@@ -52,29 +49,20 @@
     [else (inner-lex ip)]))
 
 (define-macro top #'begin)
-(define-macro (assignment ID EXPR)
-  #'(define ID EXPR))
 
 (define-macro-cases comparison
-  [(_ ARG) #'ARG]
+  [(_ LEFT "<" RIGHT) #'(< LEFT RIGHT)]
-  [(_ LARG OP RARG) #'(OP LARG RARG)])
+  [(_ OTHER) #'OTHER])
 
-(define-macro sum #'comparison)
+(define-macro (func-def VAR VARS STMT ...)
-(define-macro product #'comparison)
+  #'(define (VAR . VARS)
-
-(define-macro (func-def ID ID-ARGS STMT ...)
-  #'(define (ID . ID-ARGS)
       (let/cc return-cc
         (syntax-parameterize ([return (make-rename-transformer #'return-cc)])
           STMT ... (void)))))
 
 (define-syntax-parameter return (λ (stx) (error 'not-parameterized)))
-(define-macro func-app #'#%app)
 
-(provide (rename-out [my-for for]))
+(define-macro func-app #'#%app)
-(define-macro (my-for ID EXPR . STMTS)
-  #'(for ([ID (in-list EXPR)])
-      . STMTS))
 
 (define-macro block #'begin)
 
@@ -83,14 +71,9 @@
   [(_ COND TBLOCK) #'(when COND TRUE-BLOCK)]
   [(_ COND TBLOCK FBLOCK) #'(if COND (let () TBLOCK) (let () FBLOCK))])
 
-(provide (rename-out [my-print print]))
-(define-macro (my-print EXPR)
-  #'(display EXPR))
-
 (define (read-syntax src ip)
   (define parse-tree (parse (λ () (lex ip))))
   (strip-context
    (with-syntax ([PT parse-tree])
      #'(module _ pythonesque-demo
-         #;(pretty-print 'PT)
          PT))))

beautiful-racket-demo/pythonesque-demo/test.rkt

@@ -1,51 +1,27 @@
 #lang pythonesque-demo
 
-a = 3
+"escaped quote: middle \" and end \""
-b = 4
+"escaped backslash: middle \\ and end \\"
 
-"middle \" escaped quote"
+def nothing():
-"ending escaped quote\""
+  42
-"middle \\ escaped backslash"
-"ending escaped backslash\\"
 
-def ft():
+def fortytwo():
   return 42
 
-def gt(x, y):
+def eightyfour():
-  return x > y
+  return 84
   def noop():
-    return "double dedent here"
+    return "double dedent next"
 
+nothing() # no output
 
-def squaresum(x, y):
+if fortytwo() < eightyfour():
-  def add(c, d):
+  "left is less than right"
-    return c + d
-  return add(x, y) * add(x, y)
-
-gt(a, b) # #f
-squaresum(b, a) # 49
-
-println(a)
-
-expt(2, 4)
-
-range(1, 5)
-
-# keep indented example next to eof
-for x in range(1, 5):
-  println(x * x)
-
-def foo(x):
-  x
-
-foo(42) # no return value
-
-if a < b:
-  print "a is less than b"
 else:
-  print "a is not less than b"
+  "left is not less than right"
 
-def bar(x, y):
+def last():
-  return x > y
+  return 42
   def noop():
-    return "double dedent here"
+    return "double dedent next"