technical update

master
Matthew Butterick 8 years ago
parent da04ff8a3a
commit 2522d1e884

@ -1,5 +0,0 @@
#lang racket/base
(require pollen/private/whitespace
pollen/unstable/typography)
(provide (all-from-out pollen/private/whitespace
pollen/unstable/typography))

@ -65,7 +65,8 @@ Other libraries we'll be using. @racketmodname[sugar] and @racketmodname[txexpr]
sugar
txexpr
hyphenate
"../helper.rkt"
pollen/private/whitespace
pollen/unstable/typography
"../pricing-table.rkt")]
@ -360,10 +361,10 @@ It also makes it possible to change the fiddly HTML markup from one central loca
txexpr?]
Create a span with the class @tt{glyph}.
Here, we'll use @racket[make-default-tag-function], which is an easy way to make a simple tag function. Any keywords passed in will be propagated to every use of the tag function.
Here, we'll use @racket[default-tag-function], which is an easy way to make a simple tag function. Any keywords passed in will be propagated to every use of the tag function.
@chunk[<glyph>
(define glyph (make-default-tag-function 'span #:class "glyph"))]
(define glyph (default-tag-function 'span #:class "glyph"))]
@defproc[
@ -406,8 +407,8 @@ Our list of elements could contain sequences like @racket['("\n" "\n" "\n")], wh
(and (string? elem) (regexp-match list-item-separator-pattern elem)))
(define list-of-li-elems (filter-split elems-merged list-item-break?))
(define list-of-li-paragraphs
(map (λ(li) (detect-paragraphs li #:force? #t)) list-of-li-elems))
(define li-tag (make-default-tag-function 'li))
(map (λ(li) (decode-paragraphs li #:force? #t)) list-of-li-elems))
(define li-tag (default-tag-function 'li))
(map (λ(lip) (apply li-tag lip)) list-of-li-paragraphs))]
@margin-note{Explicit type checking — e.g., @racket[(string? elem)] — is common in Racket. You can do ``duck typing'' (see @racket[with-handlers]) but it's not idiomatic. IMO this is wise — better to have an explicit, readable test (likse @racket[string?]) rather than an implicit, indirect one (``If the input isn't a @racket[string?], then a certain error will arise.'')}
@ -417,8 +418,8 @@ Because of the expression-based structure of Racket, it's often possible to writ
@chunk[<bad-idea>
(define (detect-list-items elems)
(map (compose1 (curry apply (make-default-tag-function 'li))
(curryr detect-paragraphs #:force? #t))
(map (compose1 (curry apply (default-tag-function 'li))
(curryr decode-paragraphs #:force? #t))
(filter-split (merge-newlines elems)
(λ(x) (and (string? x)
(regexp-match #rx"\n\n\n+" x))))))]
@ -561,7 +562,7 @@ Special version of @racket[xref] for the @filepath{fontrec} subdirectory.
@defform[(define-heading heading-name tag-name)]
Macro for defining a function that makes a heading.
This could also be done with @racket[make-default-tag-function]. And as a rule of thumb, it's wise to reserve
This could also be done with @racket[default-tag-function]. And as a rule of thumb, it's wise to reserve
macros for the times you can't avoid using them. Otherwise, use a function.
We'll bend that rule here because this is a quick & easy example macro. What makes it suitable to be
@ -573,8 +574,8 @@ argument to the function. With a function, we can't do that. But with a macro, w
@chunk[<define-heading>
(define-syntax-rule (define-heading heading-name tag)
(define heading-name
(make-default-tag-function tag
#:class (symbol->string 'heading-name))))]
(default-tag-function tag
#:class (symbol->string 'heading-name))))]
``Wait, why does @racket['heading-name] not produce the literal symbol @racket['heading-name]?'' The @racket['heading-name] syntax is just shorthand for @tt{(quote heading-name)}. Because this is a macro, the @racket[heading-name] inside this expression gets replaced with the value of the macro argument @racket[heading-name] before @racket[quote] is evaluated.
@ -683,7 +684,7 @@ The idea is to break down the input into table headings and cells, and then work
(for/list ([text-cell (in-list (string-split text-row "|"))])
(string-trim text-cell)))))
(match-define (list tr-tag td-tag th-tag) (map make-default-tag-function '(tr td th)))
(match-define (list tr-tag td-tag th-tag) (map default-tag-function '(tr td th)))
(define html-rows
(match-let ([(cons header-row other-rows) rows-of-text-cells])
@ -775,12 +776,12 @@ Recall that every Pollen tag calls a function with the same name (if it exists,
Often, you'll want to use a @racket[decode] or @racket[decode-elements] function, which can recursively perform different kinds of processing on different types of page elements.
In this case, we'll use @racket[decode-elements] twice. First, we'll use it just to detect paragraphs. We'll do this so that they're treated as @seclink["Block" #:doc '(lib "pollen/scribblings/pollen.scrbl")]{blocks} in the second phase, which does the rest of the processing.
In this case, we'll use @racket[decode-elements] twice. First, we'll use it just to detect paragraphs. We'll do this so that they're treated as blocks (see @racket[block-txexpr?]) in the second phase, which does the rest of the processing.
@chunk[<root>
(define (root . elems)
(define elements-with-paragraphs
(decode-elements elems #:txexpr-elements-proc detect-paragraphs))
(decode-elements elems #:txexpr-elements-proc decode-paragraphs))
(list* 'div '((id "doc"))
(decode-elements elements-with-paragraphs
#:block-txexpr-proc hyphenate-block
@ -849,19 +850,19 @@ When I type an em dash in my sources, I will often leave a space around it, but
Presented without docs or comment, as it should be obvious at this point what they do.
@chunk[<misc-functions>
(define omission (make-default-tag-function 'div #:class "omission"))
(define omission (default-tag-function 'div #:class "omission"))
(define mono (make-default-tag-function 'span #:class "mono"))
(define mono (default-tag-function 'span #:class "mono"))
(define font-details (make-default-tag-function 'div #:class "font-details"))
(define font-details (default-tag-function 'div #:class "font-details"))
(define mb-font-specimen
(make-default-tag-function 'div #:class "mb-font-specimen" #:contenteditable "true"))
(default-tag-function 'div #:class "mb-font-specimen" #:contenteditable "true"))
(define (margin-note . xs)
`(div ((class "margin-note") ,no-hyphens-attr) ,@xs))
(define os (make-default-tag-function 'span #:class "os"))
(define os (default-tag-function 'span #:class "os"))
(define (gap [size 1.5])
`(div ((style ,(format "height: ~arem" size)))))
@ -872,9 +873,9 @@ Presented without docs or comment, as it should be obvious at this point what th
(define (indented #:hyphenate [hyphenate #t] . xs)
`(p ((class "indented"),@(if (not hyphenate) (list no-hyphens-attr) null)) ,@xs))
(define caption-runin (make-default-tag-function 'span #:class "caption-runin"))
(define caption-runin (default-tag-function 'span #:class "caption-runin"))
(define caption (make-default-tag-function 'span #:class "caption"))
(define caption (default-tag-function 'span #:class "caption"))
(define (captioned name . xs)
`(table ((class "captioned indented"))