HTMS

Everyone knows HTML, but new programmers are often intimidated by JavaScript and
its code-looking syntax. Unfortunately, HTML does not have scripting abilities
of its own. Until now!

HyperText Markup Script provides a way to express computations using just HTML.
It even provides full interoperability with JavaScript code for a smooth
transition when you feel ready to use a "real" language.

How to use HTMS:

1. Include the htms.min.js script on the page
2. Create your root element
3. Write your code!

Syntax

The formal syntax of the language is exactly the same as HTML, though the tags
have slightly different meanings.

Nodes (Tags)

####

The root HTMS node defines where to start running your HTMS code. All exported
values will be placed in a global JavaScript object with the name given by the
name attribute. (i.e. some_name, or window.some_name).

The final value of the node is automatically exported with the name
default.

``html



`

####

Provides no special purpose other than to execute its children in order. It can
be used to turn variables into strings and numbers (see and ).
`html



`

####

Assigns the final value of its children to the variable given by the name
attribute. This variable can then be referenced later by its name.

Note that there are a few built in identifiers which cannot be used as variable
names, namely true, false, and $_. These correspond to the Boolean true
and false values, and the "previous value".

$_ is often used internally, and so you should not need to reference it, but
you can. $_ always holds the value of the previously executed node in the
current block. When no nodes have yet been run in the current block, the value
of $_ is null. This is the only way to obtain the null value, which may be
useful at times.

`html

Hello world



string

`

####

Turns its final value into a string. If it is a text node, the text is used
literally. Otherwise, it is the return value of evaluating the final element.

`html
3
Hello world
x
x
`

####

Similar to but for numbers.

`html
5
3
x
x
`

####

Similar to but for Booleans.

`html
0
3
0
false
true
false
x
x
`

####

Negates its final value as a Boolean. Note that this is an operator, and not a
type constructor, so untyped values are evaluated as variables automatically and
do not require being nested in a .

`html
false
true
3
false
x
x
`

####

Produces the sum of all the elements in its final value, which must be an array
of numbers or strings. With strings, it performs concatenation.

`html




1. 3


2. 4


3. 5