Category: Link

I love my M.U.T.T.

Last Friday I took my first real ride on the bike. It was a lot of fun. Riding a bike with a 10k redline was also a new experience for me which made it fun. Honestly, it was sort of shocking to me, the engine seemed to have 3 moods:

  1. Meditating
  2. Purring
  3. Roaring!

I wondered where the engine should live for normal cruising, and Dale explained that where it seems happy, it is happy. Great. I can’t wait to get back out again to spend some time with my M.U.T.T. Who is M.U.T.T?
As Dan explained… the “Monster Under The Tank”!

Setting the background color in Slideshow

The OP asked how to set the background color in Slideshow as it is not obvious.
Matthew replied:

Locally, I’d superimpose a picture onto a color rectangle:

#lang slideshow
 (define (add-bg p color)
   (refocus (cc-superimpose
             (colorize
              (filled-rectangle (pict-width p)
                                (pict-height p))
              color)
             p)
            p))
 (add-bg (bt "Hello") "green")

To globally set the background, I’d use that in an assembler:

#lang slideshow
 (define (add-bg p color)
   (refocus (cc-superimpose
             (colorize
              (filled-rectangle (pict-width p)
                                (pict-height p))
              color)
             p)
            p))
 (current-slide-assembler
  (let ([orig (current-slide-assembler)])
    (lambda (title sep body)
      (ct-superimpose
       (inset (add-bg (inset full-page margin) "green")
              (- margin))
       (orig title sep body)))))
 (slide #:title "Example" (bt "Hello"))

(via plt)

How to evaluate expressions and produce no output in Scribble

The OP asked:

Is there a way to evaluate something in a given evaluator without having anything displayed in the output?
Ie. I want to feed a couple of basic function definitions into the evaluator instance that I obtain with (make-base-eval).

Matthew shared the solution: interaction-eval.
(via plt)

Incremental definition and evaluation of examples in Scribble

The scribble/eval library provides utilities for evaluating code at document-build time and incorporating the results in the document, especially to show example uses of defined procedures and syntax.

Here is an example where the OP was:

trying to figure out a way to insert some text in between Scheme definitions: that is, have some definitions (@schemeblock or equivalent), with their explanations (text mode), and then an interaction, like @interaction, except that it should be aware of the preceeding definitions.

Here is the solution:

#lang scribble/manual
@(require scribble/eval)
@(define ex-eval (make-base-eval))
First, we define @scheme[x]:
@interaction[
#:eval ex-eval
(define x 1)
]
Next, we use it:
@interaction[
#:eval ex-eval
x
]
@(close-eval ex-eval)

(via plt)