option for line numbers for report macro #1

I think something like this would be a nice option to have:

(define x 5)
(report x #:line) ; x = 5 at line 2

Or maybe this:

(define x 5)
(parameterize ([report-line-number #t])
  (report x)) ; x = 5 at line 3

Or maybe something where drracket can show one of those octagons with 'x's in them like it shows if you do this in drracket: (if it's possible without messing it up for other stuff)

(with-handlers ([exn:fail:syntax? (lambda (e) ((error-display-handler) "x = 5" e))])
  (raise-syntax-error #f "whatever" #'here))

I think something like this would be a nice option to have: ``` racket (define x 5) (report x #:line) ; x = 5 at line 2 ``` Or maybe this: ``` racket (define x 5) (parameterize ([report-line-number #t]) (report x)) ; x = 5 at line 3 ``` Or maybe something where drracket can show one of those octagons with 'x's in them like it shows if you do this in drracket: (if it's possible without messing it up for other stuff) ``` racket (with-handlers ([exn:fail:syntax? (lambda (e) ((error-display-handler) "x = 5" e))]) (raise-syntax-error #f "whatever" #'here)) ```

Interesting suggestion, though I have had difficulty getting keyword arguments to work smoothly in macros (perhaps it could just be (report-with-line ...).

Does parameterize work with macros? I thought it was strictly a way of manipulating the runtime namespace.

Interesting suggestion, though I have had difficulty getting keyword arguments to work smoothly in macros (perhaps it could just be `(report-with-line ...)`. Does `parameterize` work with macros? I thought it was strictly a way of manipulating the runtime namespace.

For parameterize, it can expand to code that would do something different depending on the value of the parameter.

(define-syntax (report stx)
  (syntax-case stx ()
    [(_ expr) #'(report expr expr)]
    [(_ expr name)
     #`(let ([x expr])
         (display-for-report x 'name #,(syntax-line #'expr))
         x)]))
(define (display-for-report x name line)
  (cond [(report-line-number)
         (displayln (format "~a = ~v at line ~a" name x line) (current-error-port))]
        [else
         (displayln (format "~a = ~v" name x) (current-error-port))]))

For keywords, it might be easier with syntax-parse and the seq-no-order pkg, or a report-with-line would be just as good.

For parameterize, it can expand to code that would do something different depending on the value of the parameter. ``` racket (define-syntax (report stx) (syntax-case stx () [(_ expr) #'(report expr expr)] [(_ expr name) #`(let ([x expr]) (display-for-report x 'name #,(syntax-line #'expr)) x)])) (define (display-for-report x name line) (cond [(report-line-number) (displayln (format "~a = ~v at line ~a" name x line) (current-error-port))] [else (displayln (format "~a = ~v" name x) (current-error-port))])) ``` For keywords, it might be easier with syntax-parse and the [seq-no-order](http://pkg-build.racket-lang.org/doc/seq-no-order/index.html) pkg, or a `report-with-line` would be just as good.

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option for line numbers for report macro #1