Based on: Building Your Own Programming Language From Scratch
# Make sure your environtment have a Maven installed
mvn package
mvn compile
To calculate a complex expression in the proper order, each of the supported operators has its own precedence:
| Operator | Value | Precedence | Example |
|---|---|---|---|
| Assignment | = |
1 | a = 5 |
| Append value to array | << |
1 | array << "value" |
| Logical OR | or |
2 | true or false |
| Logical AND | and |
3 | true and true |
| Left Paren | ( |
4 | |
| Right Paren | ) |
4 | |
| Equals | == |
5 | a == 5 |
| Not Equals | != |
5 | a != 5 |
| Greater Than Or Equals | >= |
5 | a >= 5 |
| Greater Than | > |
5 | a > 5 |
| Less Than Or Equals | <= |
5 | a <= 5 |
| Less Than | < |
5 | a < 5 |
| Addition | + |
6 | a + 5 |
| Subtraction | - |
6 | a - 5 |
| Multiplication | * |
7 | a * 5 |
| Division | / |
7 | a / 5 |
| Floor Division | // |
7 | a // 5 |
| Modulo | % |
7 | a % 5 |
| NOT | ! |
8 | !false |
| Class Instance | new |
8 | a = new TreeNode [ 5 ] |
| Class Property | :: |
8 | b = a :: value |
To show a general output :
| Commands | Function |
|---|---|
| help | Used to see documentation and usages |
| version | Used to see xyLang version are installed on this machine |
- Variables declaration
# Plain types
<variable name> = <expression>
a = 1
b = "Hemlo Indonesia"
# Arrays
<array> = { <value1>, <value2>, ... }
example_array = { 1, 2, "aku" }
empty_array = {}
- Conditions
nek <condition>
# Block Statement
nekngene <condition>
# Block Statement
nekora
# Block Statement
uwes
nek a > 5 and tree_node :: value == 3
# Block Statement
nekngene b == "hello" or c == "world"
# Block Statement
nekora
# Block Statement
uwes
- Print to console
ndelok <expression>
ndelok a + b + c
- Input from console
nginput <variable name>
nginput number
- Functions
guna <function name> [ <argument1, argument2>, ... ]
<body>
return <expression>
uwes
guna fibonacci_number [ n ]
nek n < 2
return n
uwes
return fibonacci_number [ n - 1 ] + fibonacci_number [ n - 2 ]
uwes
- Loops
# For loop
ngulang <variable> ing <lower_bound>..<upper_bound>
# statements
uwes
# Specify the step
ngulang <variable> ing <lower_bound>..<upper_bound> karo <step>
# statements
# seed increment statement
uwes
# While loop
ngulang <condition>
# statements
uwes
# Iterable loop (for-each)
ngulang <variable> ing <iterable>
# statements
uwes
# terminate the loop
ngulang <variable> ing <lower_bound>..<upper_bound> karo <step>
nek <other_condition>
stop
uwes
uwes
# jump to the next iteration
ngulang <variable> ing <lower_bound>..<upper_bound> karo <step>
nek <other_condition>
skip
uwes
uwes
There are the following data types currently supported:
- Numeric
number1 = 1
number2 = 2.
number3 = 3.21
number4 = 0.432
number5 = .543
number6 = -1
- Text
text = "hello world"
- Logical
logical1 = true
logical2 = false
- Class
class <class name> [ <property1>, <property2>, ... ]
# inner statements
ndelok <property1>
guna <function name> [ <property1>, <property2> ]
# function statements
this :: <property1> = <property1>
uwes
uwes
class Lamp [ type, is_on ]
guna turn_on []
is_on = true
uwes
guna turn_off []
is_on = false
uwes
guna set_is_on [ is_on ]
this :: is_on = is_on
uwes
uwes
lamp_instance = new Lamp [ "Halogen", false ]
# get/set class's property
lamp_is_on = lamp_instance :: is_on
lamp_instance :: type = "Led"
# invoke class's function
lamp_instance :: turn_off []
- Arrays
<array> = { <value1>, <value2>, ... }
example_array = { 1, 2, "three", new TreeNode [ 4 ] }
empty_array = {}
# get an array's value
<value> = <array> { <index> }
value = items{1}
# set an array's value
<array> { <index> } = <value>
items{1} = 123
# append a value to array
<array> << <value>
items = {1,2}
items << 3 #{1,2,3}
- Null
value = null