LESL 'programming language'

The LESL is current in beta, and have some bugs:

• Console highlighting is too buggy Minuses:
• LESL not have functions
• Not standart syntax

The syntax

Variables

Grammar:

name -> value

Example:

x -> 1
y -> 5

a -> 3
b -> 2

String functions

Variables has 'prototype' of string functions.

Math with variables

Variables may used in equations.

Example:

x -> 5
y -> 6

x + y * x

=> 35

Comments

# Comment

IF

a (is|not|less|more) b (and c (is|not|less|more) d)...? [ true ] : [ false ]

Example:

a not b?
=>  true
x is y? [ "OK"  ]:["NOK"]
=> NOK

Marks

name [ source ]

Call mark

name!

Example:

greeting [
	"Hello, World"
]

greeting!

=> Hello, World

from-to loop

Returns list from x to y, separated by ','

Standart

Grammar:

from x to y

Example:

from 1 to 12

=> 1,2,3,4,5,6,7,8,9,10,11

Short

Grammar:

x..y

Example:

1..12

=> 1,2,3,4,5,6,7,8,9,10,11

Math with lists

You may do math only(!) with short lists. If we look at this example:

1..5 + 1

That outputs

=> 2,3,4,5

That pluses 1 to EACH list element. If we look at another example:

1..5 ^ 4

That outputs

=> 1,16,81,256

That makes pow of EACH list element.

Numbers

Dollars

LESL have built-in dollar translation. To select course, create in root of LESL file options.json, and write content like this:

{
	dollar: 56.9
}

After this simple operation, you may do dollar translation:

  200$
=> 11611

And do with this dollars mathematical operations:

200$ + 12000 - 5000
=> 18611

Floats

Float is number with floating point.

Example:

12.5
1.3
0.6
19.4
3.14

Integers

Example:

	1
	53
	12
	75
	666
	999
	512

Strings

String is all inside double quotes, besides newlines, and double quotes.

Example:

"Hello, World"

"Hi"

"Hi, NPM"

String methods

String also has functions for operate with it.

• str.slice s, e

  Slices from start(s) position to end (e) position.

  Example:

    	"Hello".slice 2, "Hello".len
  
    	=> llo

• str.len

  Get length of str string.

  Example:

    "Hi".len
  
    => 2

• str.uppercase

  Convert string to uppercase.

  Example:

    "Alexey".uppercase
  
    => ALEXEY

• str.lowercase

  Convert string to lowercase.

  Example:

    "Alexey".lowercase
  
    => alexey

• str.capitalize

  Make first letter in string uppercase.

  Example:

    "i am here".capitalize
  
    => I am here

• str.reverse

  Reverses the string.

  Example:

    "Hello, World!".reverse
  
    => !dlroW ,olleH

• str.char i

  Get char on i index in str.

  Example:

    "Hellow".char "Hello".len
  
    => w

Include other files

To include other files, you also may use 'use' command. That imports all variables and marks from including files.

use name - String

Example:

use "core/booleans"

$> true

=>  1

$> false

=> 2

$> LESLBooleans!

=> LESLBooleans library by Alexey Yurchenko
	 true / false / yes / no  / ok / nok

Examples

Hello, World!

"Hello, World!"

=> Hello, World!

Math

12 * 2^4

=> 192

2 + 2

=> 4

Math constants library

./math_const.lesl

PI -> 3.14
E ->  2.71

./example.lesl

use "math_const"

PI

=> 3.14

E

=> 2.71

PI + E

=> 5.85

(C) Alexey Yurchenko.

Sorry for bad english.