% !TeX program = lualatex
% =====================================================================
%  02-containers.tex
%  The three layout containers, each built up from its simplest form —
%  and each shown holding what it really holds: not just text, but
%  formulas, images, lists and nested blocks. Tables, then boxes, then
%  the named-area grid that assembles a full worksheet header.
% =====================================================================
\documentclass[
  margins=18,
  size=11,
  imgdir={IMG, IMAGES/PNG}
]{scholatex}
\begin{document}

let title = <Red b 18pt c>
let h1    = <line Navy b section>
let h2    = <Teal i subsection>

<title>Simple LaTeX — containers

% =====================================================================
<h1>Tables, step by step
% =====================================================================

<h2>Bare alignment
A table with neither borders nor header is just aligned columns. Columns
are declared in brackets, one two-letter placement code per column: the
first letter is vertical (t/m/b), the second horizontal
(l/c/r). N: before the code fixes a width in mm. Here
[ml, mc, mr] sends the three columns left, centre and right; the
vertical part has nothing to do yet, since every cell is one line tall — it
comes into play once a row holds something taller, as the next table shows.
<table [ml, mc, mr]>{
	Apple | Pear | Plum
	Cat | Dog | Horse
}

<h2>Borders, header, and mixed content
borders draws the rules; header bolds the first row. A cell may
hold a formula or an image, not only text. Each column's placement is given
by a two-letter code right in the brackets: the first letter is vertical
(t top, m middle, b bottom), the second horizontal
(l/c/r). So [mc, tl, br] centres the figure in its cell, keeps the
formula top-left, and drops the value to the bottom-right — each column placed
in both directions at once. The vertical part shows whenever a row is taller
than its shortest cell, as the image below makes the formulas do.
<table [mc, tl, br] borders header>{
	Figure | Formula | Value
	<img 20>{chat.png} | $1/2 + 1/3$ | $5/6$
	<img 40>{chien.png} | $sqrt(2)$ | $1.41$
}

<h2>Spanning cells
A cell tagged <<colspan:N mc>> covers N columns; <<rowspan:N mc>>
covers N rows, and each cell it absorbs below is a lone ..
<table [mc, ml, mc, mc] borders header>{
	<colspan:4 mc>{Term report}
	Day | Subject | Mark | Coef.
	<rowspan:2 mc>{Monday} | Maths | 15 | 4
	. | French | 12 | 3
}

<h2>Colour, applied to the table itself
fill: colours the body, line: the rules, and
headerfill: / headertext: the header row — no wrapping box.
<table [mc, ml, mc] borders header gap:3 fill:AliceBlue line:Navy headerfill:Navy headertext:White>{
	Day | Subject | Mark
	Monday | Maths | 15
	Tuesday | French | 12
}

<h2>Dynamic rows
The column count is checked on every row, so loops and interpolation work
inside a table.
<table [mc, ml, mc] borders header>{
	<colspan:3 mc>{Table of squares}
	n | Caption | Square
	for n in 1..3 {
		#n | line #n | $#n^2$
	}
}

<h2>Multi-line cells
A cell can hold more than one line: the tag <<nextline>> breaks the
line where you put it, so an address or a two-part label stacks inside a
single cell.
<table [ml, ml] borders header>{
	Field | Entry
	Name | Surname: <nextline> First name:
	Address | Street and number <nextline> Town and postcode
}

% =====================================================================
<h1>Boxes, step by step
% =====================================================================

<h2>A framed note, with a formula inside
line: sets the frame, fill: the background, radius:N
rounds the corners, title: adds a bar. The body is ordinary scholatex, so
maths and styling live in it freely.
<box line:Crimson fill:MistyRose radius:4 title:{Key identity}>{
	The remarkable identity $(a + b)^2 = a^2 + 2*a*b + b^2$ holds for all
	real numbers. The <b>{cross term} $2*a*b$ is the one pupils forget.
}

<h2>Problem and solution, with an image and a list
A line holding only --- splits a box into an upper and a lower part.
Either part may hold anything — here an image up top, a numbered method below.
<box line:DarkSlateGray fill:WhiteSmoke radius:2 title:{Problem}>{
	<c>{<img 22>{chat.png}}
	Measure the cat's height in the picture, to scale 1:10.
	---
	<list:decimal>{
		Read the height in millimetres.
		Multiply by 10.
		Give the answer in centimetres.
	}
}

<h2>Boxes side by side, holding different things
<<row>> lays its child boxes in equal-width, equal-height columns. One
holds prose, the other a formula and an image — the columns still align.
<row gap:5>{
	<box line:Crimson fill:MistyRose radius:2 title:{Statement}>{
		<tab>The perimeter of a right triangle with legs of lengths 3 and 4 is found to be 12 units by first calculating the hypotenuse using the Pythagorean theorem.
		<tab>The calculation shows that the hypotenuse is 5, leading to a total perimeter of 12.
	}
	<box line:Navy fill:AliceBlue radius:2 title:{Result}>{
		Hypotenuse: $sqrt(3^2 + 4^2) = 5$.
		<c>{<img 18>{chien.png}}
	}
}

<h2>A reusable component
The factoring tool at the block level: define a card once, call it with
arguments, and its call-site body — formulas included — becomes the content.
let exo{n} = <box title:{Exercise #n} line:Navy fill:AliceBlue radius:2>
for n in 1..2 {
	<exo #n>{
		Compute $#n^2 + #n$ and write the result below.
		<2lines>
	}
}

% =====================================================================
<h1>Grid: a named-area layout
% =====================================================================
The grid arranges named areas like CSS Grid. The template draws the layout
with one word per cell; a name repeated across cells spans them. Each
<<area>> takes the same box options and a two-letter placement code,
and — like a box — holds text, maths, images, lists or nested blocks. Here
the header spans two columns, the figure panel two rows, and the body the
full width.
<grid template:[
	"head head fig"
	"intro rules fig"
	"body body body"
] gap:3 width:100% height:95>{
	<area head mc line:Navy fill:AliceBlue radius:2 title:{Assessment}>{
		<b 14pt>Mathematics — Year 9
	}
	<area fig mc line:Crimson fill:MistyRose radius:2 title:{Figure}>{
		<img 30>{chien.png}
	}
	<area intro line:Teal fill:LightCyan radius:1>{
		Time: 50 min. No calculator.
	}
	<area rules line:Goldenrod fill:LightYellow radius:1>{
		<list:check>{
			Show every step
			Box your answers
		}
	}
	<area body j line:DarkSlateGray fill:WhiteSmoke radius:2 title:{Exercise 1}>{
		Solve $2*x + 3 = 7$ and check that $x$ satisfies $x > 0$.
	}
}

<h1>Nesting and many-line titles
A container holds anything another container holds, so blocks nest as deep
as the page allows. A centred, bold figure stacks three tags whose closing
braces all meet at the end --- and the layout still resolves cleanly.
<box line:DarkSlateGray fill:WhiteSmoke radius:2 title:{Deep nesting}>{
	<c>{<b>{<img 18>{chien.png}}}
	Centred, bold, framed: three closing braces in a row, no ambiguity.
}

A box title is ordinary text, so it may run across several lines and carry
any character --- including a chevron that has nothing to do with a tag:
<box line:Crimson fill:MistyRose radius:3 title:{threshold a > b,
checked on two lines}>{
	The title wrapped onto a second line and held a literal $>$ sign.
}


\end{document}