#[
A paragraph is a document-structural object, like a section or a table of
contents, and making paragraphs is a service @document provides: inside a
@document, blank-line-separated text becomes paragraphs (the LaTeX
convention) and @par need not be written.  @par is the explicit form, for
a text FRAGMENT rendered without a @document, where nothing infers them.
Written inside a @document it is harmless: html sees a <p>, which the
paragraph pass recognizes as a block and leaves alone, and \par in
vertical mode is a no-op.
]#

# Paragraph

@@par.k s : A paragraph of text. @@

@@par.html :: <p>*s*</p> @@

@@par.tex :: \par *s* \par @@

# In plain text a paragraph is delimited by blank lines, which
# phases.justify_blocks then fills; #/2 inserts them without depending on
# the definition body's own whitespace surviving extraction.
@@par.txt :: #/2*s*#/2 @@


# Non-breaking space

@@sp.k : Non-breaking space character @@
@@sp.html :: &^#160; @@
@@sp.tex :: ~ @@

# Indented block

@@indent.k s :left.int 8 :right.int -1 :ragged.bool false :
Indented block. The *left* and *right* values are the number of characters for
indentation (as roughtly defined by "ex"). By default, *right* is set to the
*left* value (with -1 as the sentinel).
@@
@@indent.html,tex,txt :: @eval block.Indent(K) eval@ @@


# Right justification

@@right.k s :margin 0 :top_margin 2 :  Right-justified text @@

@@right.html ::
<div style="text-align: right; margin: *top_margin*ex *margin*ex 2ex 0;">*s*</div>
@@

@@right.tex ::
{\setlength{\topsep}{0pt}\setlength{\partopsep}{0pt}\setlength{\parskip}{*top_margin*ex}
\begin{flushright}
\raggedleft\rightskip=*margin*ex
*s*
\end{flushright}}
@@

@@right.txt ::
  @eval import textwrap; "\n".join([line.rjust(*Target_txt_width*, "~")
        for line in textwrap.wrap("""*s*""", *Target_txt_width*)]) @
@@


# Quote with attribution

@@quote.k text | attribution :  A block quote with attribution. @@
@@quote.html,tex ::
  @indent *text* :left 8 @
  @right *attribution* :margin 8
         :top_margin @cond @eval "*K_target*" == "html" @ | -1 | 1 cond@ @
@@  


# Highlighted note in text

@@note.k s :label Note :color 1.0,1.0,0.9 :border_color 0.2,0.2,0.2 :level.int 0 :width.float 0.5
  : Rectangular block for an editorial note @@

@@note.html,tex :: @eval block.Note(K) @ @@


# Center

@@center.k s : Center text @@

@@center.tex ::
\begin{center}
*s*
\end{center}
@@

@@center.html ::
<p>
<div class="center">
*s*
</div>
</p>
@@


# Newline

@@nl.k : Newline character @@
@@nl.html :: <br/> @@
@@nl.tex :: \newline @@
@@nl.txt :: @eval phases.txt_nl_marker() @ @@


# New page

@@newpage.k : Start new page @@
@@newpage.html :: @@
@@newpage.tex :: \newpage @@
@@newpage.txt :: @@


# Extend page

@@extendpage.k linecount : Extenad current page @@
@@extendpage.html :: @@
@@extendpage.tex :: \enlargethispage{*linecount*\baselineskip} @@
@@extendpage.txt :: @@


# Vertical space

@@vspace.k lines.float : Vertical space, in multiples of the current line height @@
@@vspace.tex :: \vspace{*lines*\baselineskip} @@
@@vspace.html :: <div style="height: *lines*lh"></div> @@
@@vspace.txt :: @eval phases.txt_vspace_marker() * round(*lines*) @ @@

# Vertical fill to end of page

@@vfill.k :
Fill the vertical space so that any following text is flush with the bottom
of the page (in HTML, the bottom of the window; once the content is taller
than the window the space collapses, as on a full LaTeX page).  Several
vfills divide the space equally, like LaTeX's \vfill glue.  In plain text,
only makes some vertical space. @@
@@vfill.tex :: \vfill @@
# An empty glue div; block.css gives it flex-grow 1 and makes the text
# column a flex column only in documents that use it (the :has() rule).
@@vfill.html :: <div class="vfill"></div> @@
@@vfill.txt :: @vspace 3 @ @@


# Questions and answers

@@qa.k question | answer : Question and answer formatting @@
@@qa.html,tex,txt ::
@b Q: @ *question*

@b A: @ *answer*
@@


# Absolute positioning

@@@argtype coords | x and y coordinates :pattern 'float'\s+'float' @@@

@@block.k : to.coords | content :width.float .5 :point.coords 0.0 0.0
: Absolute positioning of text block @@

@@block.tex :: @eval block.Block(K) eval@ @@


# Preserved line endings

@@lines.k s : Maintain line breaks @@
@@lines.html,tex,txt :: @eval block.Lines(K) eval@ @@


# Multiple columns of text

@@multicolumn.k s :n 2 :gap 3 : Format *s* in *n* columns (default: 2). The *gap* is in "ex" units.  @@

@@multicolumn.tex ::
{\setlength{\columnsep}{*gap*ex}
\setlength{\multicolsep}{\parskip}
\begin{multicols}{*n*}
*s*
\end{multicols}}
@@

@@multicolumn.html ::
  <p>
  <div style="column-count: *n*; column-gap: *gap*ex; text-align: justify;">
  *s*
  </div>
  </p>
@@


# Text justified left and right on one line

@@left_right.k parts.rest(2) :
Pairs of text left- and right- justified.  First, left lines are written with a
bar (|) between each line. Then, two bars (||), and the right lines with a bar
betwen them.
@@

@@left_right.html,tex :: @eval block.Left_right(K) @ @@


# Footnote

@@footnote.k s : Footnote @@
@@footnote.html :: <kt-footnote>*s*</kt-footnote> @@
@@footnote.tex :: \unskip\footnote{*s*} @@
@@footnote.txt :: __  #- @eval phases.txt_footnote_marker() @ *s* @eval phases.txt_footnote_marker() @ #- __ @@

# This doesn't work, either, so it isn't the @eval:
# @@footnote.txt :: __  #- marker *s* marker #- __ @@