Chap is an easy to learn, dynamic, interpretive, isolated, and keyword-less scripting language written in Rust. It is useful when you want your non-programmer users to control some stuff dynamically and perform some custom calculations in a safe sandbox.
Syntax is something between Lisp, Assembly and PHP.
ChapApp is a Chap Editor/Compiler on Browser (Powered by WASM). ChapApp is written in Rust(Dioxus) as well. Open ChapApp in a new tab.
- Why was it named 'Chap'?
- Features
- Keywords
- Syntax
- Operators
- ControlFlow
- Samples
- Data Types
- Installation
- How to use
- TODOs for version 3.0.0
- Builtin function
Rust or راست in persian means right and Chap or چپ means left.
If you code in rust(right) too much, you gradually become capitalist after a while. So you need to write some chap(left) to escape from the matrix.
Chap unlocks Two-Dimensional Full Stack Development. Front⬆️End, Back⬇️End, Rust➡️End, Chap⬅️End.
- Easy to learn.
- Cross platform (It runs on Linux, MacOS, Windows, Web(WASM))
What makes a programming language hard to learn?
"Keywords"
| Language | Keywords | Difficulty level |
|---|---|---|
| C# | 102 | 5/5 |
| Java | 48 | 4/5 |
| Python | 35 | 3/5 |
| Lua | 22 | 2/5 |
| Chap | 0 | 0/5 |
There are no keywords in Chap.
A normal line of code in chap has 3 chunks separated with -> operator:
chunk1 -> chunk2 -> chunk3
| Chunk 1 | Chunk 2 | Chunk 3 |
|---|---|---|
| input params | function name | output variable |
param1, param2 -> function_name -> $output_variable
For example:
1, 2 -> add -> $sum
- 1 and 2 separated by "," are input params.
- These input params are moving to "add" function
- Finally $sum is a variable that holds the add result in it.
Note: "add" is not a keyword, it's a builtin function.
English language is a "left to right" (aka LTR) language, and programming languages should follow the same rule, right?
Wrong:
// c base languages:
result = send(sqrt(1 + 2).toString());
↑ ↑ ↑ ↑ ↑
5 4 2 1 3// chap
1,2 -> add -> sqrt -> to_string -> send -> $result
↑ ↑ ↑ ↑ ↑
1 2 3 4 5
This is actually left to right like normal english.
Note: "Piping" is added in version 2.0.0
Make a comment with // and anything you write on the right side will be ignored.
1, 2 -> add -> $sum // this is a comment
You can write many lines of code in one line by using ;
1 -> $a; $a, 2-> sum -> $b; $b -> print -> $_
Input params are separated by comma character ",".
Input params can be:
- Variable
- String with " character around like: "hello world"
- Int just a number: 5
- Float just a normal form of floating point number 3.14
- Bool is a boolean value which is a true or false
- Tags start with @. (more on control flow)
$a, "hello", 5, 3.14, false -> function_name -> $output_var
Function names are not case-sensitive.
Function names are not sensitive about anything else:
// to_string = ToString = TOSTRING = to string = t o s t r_i_n_g
Variables should start with $ which is known as the most loved feature of PHP.
Variable name rules:
$12 // Ok
$sp a ce // OK
$#^3 // Ok
$a,b // comma not allowed
$really? // question mark at the end not allowed
$rea?lly // OK
$some->thing // -> is not allowed
If a function has no output variable you can remove chunk3:
"hello world" -> print
↑ ↑ ↑
input function removed chunk3
If a function has no input param you can remove chunk1:
input -> $user_input
↑ ↑ ↑
nothing function output
Removing chunk2 (function name) means assigning a variable:
1 -> $variable
// it's actually short for:
1 -> assign -> $variable
If a function has no input param and output_var you just write function name:
exit
If a function has output var but you removed chunk3 the result of function will get printed:
1, 2 -> add
// it's short for:
1, 2 -> add -> $temp
$temp -> print
If you just write some params. chap will print them:
1, 2
// result: 1, 2
// or
$a
// prints whatever $a is
We have the world's smallest hello world:
"Hello World"
I wish I could remove double quotes too :)
Sometimes you have a collection of function calls like this:
1, 2 -> add -> $tmp1
$tmp1 -> sqrt -> $tmp2
$tmp2 -> print
As you can see, output of a function call is input of the next function call.
In this case, you can use piping syntax to write functions next to each other and get rid of temp variables:
1, 2 -> add -> sqrt -> print
You can't use Piping when one of the functions has more than one param.
1,2 -> add -> add -> print
↑
This needs two input params
In this case you can use Parentheses:
(1,2 -> add), (3 -> sqrt) -> add -> print
This converts two:
1,2 -> add -> $TMP1
3 -> sqrt -> $TMP2
$TMP1, TMP2 -> add -> print
There is one operator -> which moves data from left to right and it is language logo.
Why are operators bad?
Because they behave different with different types.
Look at this python example:
number = input("Enter a number:")
result = number * 5 # multiply number by 5
print(number, "* 5 =", result)Following code has a bug and the result will be:
Enter a number: 3
3 * 5 = 33333
# no runtime errorWhy? Because Python uses the same operator for math.multiply and strings.repeat.
So * operator is not a type safe operator and it will do unexpected things when your forget to pass the right type to it and it will happen without throwing runtime errors (which is bad).
Same code in Chap:
input -> $number
$number, 5 -> multiply -> $result
$result
// error in line 2: multiply function works only with numbers int and float
Runtime errors are much better than logical errors, and in chap we have the repeat function:
"foo ", 3 -> repeat
// foo foo foo
In many languages "+" operator has the same problem:
# Python
def add(a, b):
a + b # concat or add? both?
add("1", "2") # 12
add(1, 2) # 3// Chap:
"1", "2" -> concat // 12
1, 2 -> concat // 12 // you can concat integers safely
1, 2 -> add // 3
"1", "2" -> add // runtime error
You can put a ? at the end of a line to debug that line:
1 -> $a
2 -> $b
$a, $b -> add? -> $c
// result 1, 2 -> add -> 3
Chap also has a function called "dump" which prints every variable you have.
You can create a tag like this:
@tag_name
And you can jump to it:
@tag_name -> jump
// or
@tag_name, true -> jump_if
// or
@tag_name, 1, 1 -> jump_if_equal
// or
@tag_name, 1, 0 -> jump_if_not_equal
Jumping backward makes loops:
@l
"Hello until your battery dies"
@l -> jump
@i, 1, 1 -> jump_if_equal
"this will not print"
@i
Note: Indention is not necessary
Initialize:
[1 2 3 4] -> $myArray
Insert:
$myArray, 5 -> insert
Pop:
$myArray-> pop -> $last_item
Get item by index:
$myArray, 1 -> get -> $first_item
// arrays index start from 1
"Hello world"
Hello world0 -> $counter
@l
$counter -> increase
@l, $counter, 100 -> jump_if_not_equal
$counter
1001,10 -> random_number -> $answer
@loop
input -> $guess
$guess -> to_int -> $guess
@win, $answer, $guess -> jump_if_equal
"wrong"
@loop -> jump
@win
"you win"
1
wrong
2
wrong
3
you win0 -> $counter
@loop
$counter -> increase
(" ", (10, $counter -> minus) -> repeat),
("*", ($counter, 2 -> multiply) -> repeat) ->
cat
@loop, $counter, 10 -> jump if not equal
**
****
******
********
**********
************
**************
****************
******************
********************
// Editable
0 -> $counter
@loop
$counter -> increase
$counter, 1 -> multiply -> $stars_size
19, $counter -> minus -> $space_size
" * ", $stars_size -> repeat -> $stars
" ", $space_size -> repeat -> $spaces
$spaces, $stars -> cat
"`*-", $stars_size -> repeat -> $stars
" ", $space_size -> repeat -> $spaces
$spaces, $stars -> cat
@loop, $counter, 10 -> jump if not equal
3 -> $c
@loop
$c-> increase
$c, 2 -> multiply -> $stars_size
22, $c-> minus -> $space_size
"*", $stars_size -> repeat -> $stars
" ", $space_size -> repeat -> $spaces
$spaces, $stars -> cat
@loop, $c, 7 -> jump if not equal
*
`*-
* *
`*-`*-
* * *
`*-`*-`*-
* * * *
`*-`*-`*-`*-
* * * * *
`*-`*-`*-`*-`*-
* * * * * *
`*-`*-`*-`*-`*-`*-
* * * * * * *
`*-`*-`*-`*-`*-`*-`*-
* * * * * * * *
`*-`*-`*-`*-`*-`*-`*-`*-
* * * * * * * * *
`*-`*-`*-`*-`*-`*-`*-`*-`*-
* * * * * * * * * *
`*-`*-`*-`*-`*-`*-`*-`*-`*-`*-
********
**********
************
**************
1 -> type_of
int
3.14 -> type of
float
"ali" -> TypeOf
string
true -> type
boolean
-> [1 2 3] -> type
list
git clone https://github.com/ali77gh/Chap
cargo build --release
sudo cp ./target/release/chap /usr/bin❯ chap
-> "hello world"
hello world
-> ❯ chap number_guess_game.chp
1
wrong
2
wrong
3
you win answer was: 3cargo build --release --libTODO
- Arrays
- fix: 'random' module will not work on WASM
- eval function
- ChapApp
- Piping syntax (1, 2 -> add -> toString -> print)
- Parentheses (1, 2 -> add), (2, 3 -> add) -> concat -> $var // 35
- New debugger syntax 1,2 -> add? -> $sum
- Fix floating point 0.2, 0.1 -> add -> $a // 0.3
- Better Closure gen for:
- Static analyzer
- Performance improvement
- Chap to C compiler (C has jumps BTW) + (executable or standard lib(dll|so|wasm) with extern)
- Update is_prime results
- Chap library for other programming lanuages
- Error Handling (backward compatible): 1, 0 -> divide -> $result, err // if you catch error like this it will prevents throwing error and give you the message.
runtime/builtin_function
Chap has 49 builtin function(version 2.0.0) (less than Java's keywords)
| Names | Input params | output | description |
|---|---|---|---|
| assign | any | any | put a value or variable in other variable 1 -> $a |
| std_out, print, show | any, any, any,... | any | prints params to console |
| std_in, input | nothing | string | read user input from console |
| exit, quit, kill, end | nothing | nothing | ends execution |
| jump | @tag | nothing | moves executor curser to closest tag with specfied name |
| jump_if | @tag, bool | nothing | jumps to tag if 1st param is true |
| jump_if_not | @tag, bool | nothing | jumps to tag if 1st param is false |
| jump_if_equal, jeq | @tag, any, any | nothing | jumps to tag if 2th and 3th params are equal |
| jump_if_not_equal, jneq | @tag, any, any | nothing | jumps to tag if 2th and 3th params are not equal |
| new_tag | @tag | nothing | creates tag (you can call this just by writing tag name |
| add | num, num | num | adds two numbers 1 + 2 = 3 or 1.5 + 1 = 2.5 |
| add_many, add_all | num, num, num,... | num | adds many numbers 1 + 2 + 3 = 6 |
| minus | num, num | num | minus two numbers 3 - 2 = 1 |
| multiply | num, num | num | minus two numbers 3 * 2 = 6 |
| divide | num, num | num | divede two numbers 3 / 2 = 1.5 |
| modulus, mod | num, num | num | divide remaining 3 / 2 = 1 |
| power, pow | num, num | num | power 3 ** 2 = 9 |
| square_root, sqrt | num | num | square root 9 -> sqrt -> 3 |
| increase, inc | $num | nothing | adds one to variable short form of: $a,1 -> add -> $a |
| decrease, dec | $num | nothing | minus one from variable short form of: $a,1 -> minus -> $a |
| equal, eq | any, any | bool | true if 1st and 2nd are equal and false if they are not |
| not_equal, neq | any, any | bool | true if 1st and 2nd are not equal and false if they are |
| and | bool, bool | bool | and logical gate |
| or | bool, bool | bool | or logical gate |
| not | bool | bool | not logical gate |
| greater_than, gt | num, num | bool | true if 1st param is bigger than 2nd param 3,2 -> true |
| less_than, lt | num, num | bool | true if 1st param is less than 2nd param 3,2 -> false |
| concat, cat | any, any | string | convert inputs to string and concat them "al","i" -> "ali" |
| repeat | any, int | string | convert inputs to string and repeat "a",3 -> "aaa" |
| length, len | any | int | convert input to string and returns length 456 -> 3 |
| contains, has | any | bool | convert inputs to string and returns 1st contains 2nd 11,1->true |
| slice, sub_string | any, int, int | string | "hello", 1, 3 -> "el" |
| insert | array, any | nothing | insert an item to list |
| get | array, int | any | get nth item of list second param is index of item |
| pop | array | any | remove last item of list and returns it |
| last | array | any | return lsat item of list (without removin it) |
| has | array, any | bool | check if an item exist in a list |
| remove | array, any | nohting | removes a given item from list |
| remove_at | array, int | nothing | removes item at index of second param |
| index_of | array, any | int | search for an item on list and returns index |
| to_string | any | string | convert input to string 1 -> "1" |
| to_float | string | float | convert input to float "1.5" -> 1.5 ; "a"->error |
| to_int | string | int | convert input to int "1" -> 1 ; "a"->error |
| dump, dump_memory | nothing | nothing | prints all variables with values |
| type_of, type | any | str | prints type of param 1 -> int; "s" -> string |
| now_sec, now, unixtime | nothing | float | unix time standard in seconds |
| wait_mil, wait_millis | int | nothing | delay code execution for 1st milliseconds |
| wait_sec, wait_sec | int | nothing | delay code execution for 1st seconds |
| wait_min, wait_minute | int | nothing | delay code execution for 1st minutes |
| wait_hour,wait_hour | int | nothing | delay code execution for 1st hours |
