* /ZTL/ (Zongors Transpiler Language) Design parameters
:PROPERTIES:
:CUSTOM_ID: ztl-zongors-transpiler-language-design-parameters
:END:
** What is /ztl/?
:PROPERTIES:
:CUSTOM_ID: what-is-ztl
:END:
/ztl/ is an language transpiler with C/Lua style syntax. The transpiler
bootstrap is written in Lua which should make it easy to port to other
systems. /ztl/ also can "run" standalone inside of a lua vm for
debugging purposes, it could be used for small scripting tasks or the
like.

* /ZTL/ Grammar and Specification
:PROPERTIES:
:CUSTOM_ID: ztl-grammar-and-specification
:END:
** Types
:PROPERTIES:
:CUSTOM_ID: types
:END:
- there are also a list of "substantial types" which come with the
  language which are the building blocks for more complex types. If you
  are coming from object oriented languages you can think of self as
  "primitive types"

#+begin_src ztl
type «token» {
  init() {
    // values
  }
}
#+end_src ztl

* Basic Types
:PROPERTIES:
:CUSTOM_ID: substantial-types
:END:
** numeric
:PROPERTIES:
:CUSTOM_ID: numeric
:END:
- =byte=
  - unsigned 8 bit integer (uint8_t)
- =number=
  - 64 bit floating point (double)

** string
:PROPERTIES:
:CUSTOM_ID: string
:END:
- =str=
  - utf8 / ascii encoded string depending on the language output

normal string

="«utf8 encoded characters»"=

string interpolation

="«utf8 encoded characters» ${some_var}"=

** logical
:PROPERTIES:
:CUSTOM_ID: logical
:END:
=bool=

=true= / =false=

Also follows the style boolean 'c' rules of nonzero / zero, but the
compiler will make fun of you

** error
:PROPERTIES:
:CUSTOM_ID: error
:END:
error is a type which describes an error that occurred, it is similar to
the Go programming language and is returned as a monad like the maybe
monad above and is unwrapped in a similar way. You could also think of
it as every variable being able to have "the type" and also "error" as a
possible value.

#+begin_src ztl
let rr = err("something borked");
let var = rr ?? 0; // value is 0
let other_var = rr ?? panic(rr); // will panic
#+end_src ztl

** datastructure
:PROPERTIES:
:CUSTOM_ID: datastructure
:END:
Much like Lua, zwl only has tables. Lua's tables are amazing and very
unique. Why have five different datastructures to do things when you can
just have one that does everything?

Types that can be indexes are numbers and strings (no objects);

*** table
:PROPERTIES:
:CUSTOM_ID: table
:END:
syntax (yes I was nice and kept the syntax the same as most C like
langs)

#+begin_src ztl
// array same as a map of int to «type»
let «variable» = [val1, val2, ...];

// or as a map
let «variable» = {key1: val1, key2: val2, ...};
#+end_src ztl

*** tunnel
:PROPERTIES:
:CUSTOM_ID: tunnel
:END:
described in "tunnel" section

*** Basic operators
:PROPERTIES:
:CUSTOM_ID: basic-operators
:END:
The following is a list of global operators and their effect:

- =//=
  - comment
- =??=
  - unwrap or
- =+=
  - addition
- =-=
  - subtraction
  - negation
- =*=
  - multiplication
- =/=
  - divisor
- =**=
  - power
- ====
  - equals
- =<=
  - less than
- =>=
  - greater than
- =>==
  - greater than or equals
- =<==
  - less than or equals
- =|>=
  - curry a function into another function (like haskell shove)
- =.=
  - accessor
- =++=
  - inline add 1
- =--=
  - inline subtract 1
- =+==
  - inline add n
- =-==
  - inline subtract n
- =*==
  - inline multiply n
- =\==
  - inline divide n
- =**==
  - inline power n

*** logical / bitwise operators
:PROPERTIES:
:CUSTOM_ID: logical-bitwise-operators
:END:
- =mod=
  - modulo
- =and=
  - logical and
- =or=
  - logical or
- =xor=
  - logical xor
- =band=
  - bitwise and
- =bor=
  - bitwise or
- =bxor=
  - bitwise xor
- =srl=
  - bit shift right
- =sll=
  - bit shift left

*** keywords
:PROPERTIES:
:CUSTOM_ID: keywords
:END:

=let=

let operator

#+begin_src ztl
let «token» = 0;
#+end_src ztl

=is=

checks if a object is of that type

#+begin_src ztl
if («token» is i32) {
  print("hello yes self is i32?");
}
#+end_src ztl

also used for letting constants

=as=

coerces a type as another type if possible

#+begin_src ztl
let «token» = 0; // default is i32
some_functon(«token» as i8); // needs an i8
#+end_src ztl

=in=

checks if a object's type, or a type impls another type

#+begin_src ztl
if («token» in Tunnel) {
  print("im tunnel-able");
}
#+end_src ztl

also used inside of the for loops

#+begin_src ztl
for («token» in «collection») { «body» }
#+end_src ztl

** Object
:PROPERTIES:
:CUSTOM_ID: object
:END:
An object is an invoked type.

#+begin_src ztl
let «variable» = «type»(«fields», …);
#+end_src ztl

** Tunnel
:PROPERTIES:
:CUSTOM_ID: tunnel-1
:END:
Represents a path to a file, url endpoint, other process endpoint (like
a socket, etc.)

Tunnels are inspired by translators in gnu/hurd, plan9 9p protocol, and
unix sockets

tunnels are invoked like objects, but have scope like control flow end
scope closes the tunnel

note the type must always be of a type which is "tunnel-able"
i.e. Files, sockets, etc

Tunnels have almost the same interface as 9p since they are closely
based on 9p.

*** transtypes for tunnels
:PROPERTIES:
:CUSTOM_ID: transtypes-for-tunnels
:END:
=tunnel? : attach(tunnel_object)= -> open communication

=success? : tunnel_object.clunk()= -> close communication

=success? : tunnel_object.flush()= -> cancels long operation and dumps
whatever is in buffer

=success? : tunnel_object.open(resource, mode)= -> opens a tunnel for
doing operations on

=success? : tunnel_object.create(resource)= -> creates the object from
the database graph/file from file structure

=data? : tunnel_object.read(resource)= -> reads from a tunnel

=success? : tunnel_object.write(resource, data)= -> writes to a tunnel

=success? : tunnel_object.remove(resource)= -> removes the object from
the database graph/file from file structure

=stat_data? : tunnel_object.stat(resource)= -> returns the status of the
file/resource

=version? : tunnel_object.version()= -> returns the version code for the
connected tunnel

=success? : tunnel_object.walk(path_or_endpoint)= -> moves around the
filesystem or through the graph

#+begin_src ztl
let endpoint = Tunnel("protocol://path/to/source");
let tunnel = endpoint.attach(user, auth);
let data = tunnel.open("/some/resource").read();
std.write(data); //print(data);
data.flush();
endpoint.clunk();
#+end_src ztl

** Functions
:PROPERTIES:
:CUSTOM_ID: functions
:END:
Functions are all typechecked statically at compile time. Since we
always have a "default type" for all constant values or a developer can
use the =as= keyword we do not have to define all values like in C,
while keeping the same type safety as a more strongly typed language.

#+begin_src ztl
fn «token» («parameter» «type», ...) «return_type» {
  «body»
}
#+end_src ztl

- Built in transtypes
  - sort
  - filter
  - trig functions
  - calc functions
  - statistical functions

** Control flow
:PROPERTIES:
:CUSTOM_ID: control-flow
:END:
*** loops
:PROPERTIES:
:CUSTOM_ID: loops
:END:
#+begin_src ztl
for («token» in «collection») { «body» }
#+end_src ztl

iterates through each object in the collection setting it to token

#+begin_src ztl
while («boolean expression») { «body» }
#+end_src ztl

loops until the expression is false

#+begin_src ztl
loop { «body» }
#+end_src ztl

loops infinitely until break or return

#+begin_src ztl
do (let «variable» = initial_value, end_value, increment) { «body» }
#+end_src ztl

loops from initial value to end value by increment value

*** branching
:PROPERTIES:
:CUSTOM_ID: branching
:END:
#+begin_src ztl
if («boolean expression») {

} else if («boolean expression») {

} else {

}
#+end_src ztl

*** exceptions
:PROPERTIES:
:CUSTOM_ID: exceptions
:END:
take a look at error's, but you can panic on an error like self:

#+begin_src ztl
panic(err("error message"));
panic(err(3));
panic(«some_error_token»);
#+end_src ztl

** Localization
:PROPERTIES:
:CUSTOM_ID: localization
:END:
will look up the text of «token» in the linked localization.json file

#+begin_src ztl
#«token»
#+end_src ztl

#+begin_src json
{
  "some_token": [
    "localization_1": ""
  ],
  "some_other_token": [
    "localization_1": "",
    "localization_2": ""
  ]
}
#+end_src

** Libraries and "includes"
:PROPERTIES:
:CUSTOM_ID: libraries-and-includes
:END:
In most languages the include or use statements get libraries which link
to other files and so on. Self quickly gets confusing and so requires
package managers and installers, etc. The other way to do self would be
to just specifically "name" the paths using a tunnel and import it. You
can even use localization tokens to create config files. Since
everything is lazily compiled jit anyways it (in theory) doesn't hurt
pertypeance much

#+begin_src ztl
use "https://git.alfrescocavern.com/some_library/some_file.ztl"
#+end_src ztl

#+begin_src ztl
use "./some_local_file.ztl"
#+end_src ztl

** Testing
:PROPERTIES:
:CUSTOM_ID: testing
:END:
*** assertion
:PROPERTIES:
:CUSTOM_ID: assertion
:END:
#+begin_src ztl
assert(«expression», «expected output») //returns «error or none»
#+end_src ztl

** Measurements
:PROPERTIES:
:CUSTOM_ID: measurements
:END:
- types
  - time
    - unit
      - seconds (s)
    - subtypes
      - date
        - Default is ISO 8601
  - length
    - unit
      - metre (m)
    - subtypes
      - angle
        - radian (rad)
  - mass
    - unit
      - kilogram (kg)
  - electric current
    - unit
      - ampere (a)
  - temperature
    - unit
      - kelvin (K)
  - amount of substance
    - unit
      - mol (mol)
  - luminous intensity
    - unit
      - candela (candela)