give an error for the ambiguous syntax "let x = 1 y = 2 ..."

src/julia-parser.scm

@@ -484,7 +484,7 @@
  (begin
  (if (not (or (eof-object? t) (eqv? t #\newline) (memv #\, ops)
  (memv t closers)))
- (error "extra token after end of expression"))
+ (error (string "extra token \"" t "\" after end of expression")))
  (if (or (null? ex) (pair? (cdr ex)) (not first?))
  ;; () => (head)
  ;; (ex2 ex1) => (head ex1 ex2)
@@ -555,7 +555,7 @@
  ;; check for unparsed junk after an expression
  (let ((t (peek-token s)))
  (if (not (or (eof-object? t) (eqv? t #\newline) (eq? t #f)))
- (error "extra token after end of expression")))
+ (error (string "extra token \"" t "\" after end of expression"))))
  ex))
 
 (define (parse-eq s)
@@ -897,13 +897,15 @@
  ((else) (list 'if test then (parse-resword s 'begin)))
  (else (error (string "unexpected " nxt))))))
  ((let)
- (let* ((binds (if (memv (peek-token s) '(#\newline #\;))
- (begin (take-token s)
- '())
- (parse-comma-separated-assignments s)))
- (ex (parse-block s)))
- (expect-end s)
- `(let ,ex ,@binds)))
+ (let ((binds (if (memv (peek-token s) '(#\newline #\;))
+ '()
+ (parse-comma-separated-assignments s))))
+ (if (not (or (eof-object? (peek-token s))
+ (memv (peek-token s) '(#\newline #\; end))))
+ (error "let variables should end in ; or newline"))
+ (let ((ex (parse-block s)))
+ (expect-end s)
+ `(let ,ex ,@binds))))
  ((global local)
  (let* ((const (and (eq? (peek-token s) 'const)
  (take-token s)))