BigAdd language is a small programming language that has been designed in order to add and subtract big integers programmatically and display the result on the screen. BigAdd is an interpreted language. The BigAdd interpreter works from the command line with the command BA, and takes the script file’s name as the only attribute. The script file is assumed to have the extension .ba .

example:

c:\> ba myscript

Point (‘.’) is the end of line character. Lines can contain keywords, brackets, variables and constants. Any number of spaces or comments can be used between these elements. A program line can be divided between multiple text lines.

A line of code is one of the following:

• A variable declaration.
• An assignment statement.
• An addition statement.
• A subtraction statement.
• An output statement.
• A loop statement.

Comments are written between curly braces { }

example:

{this is a comment}{ and
this is a comment too}

The only data type for variables is the integer. Integer is a signed whole number that is represented as a decimal data type. An integer can be as big as 100 decimal digits. Strings exist only as constants and are used in the out statements only.

example:

• 123113, -5, 0, -314159 are valid integer representations.

• 3.14159 is not a valid integer (it is a real number)
• 3.0 is not a valid integer (decimal point should not be displayed)
• 3. is not a valid integer (decimal point should not be displayed)
• - 5 is not a valid integer (there should be no blank between the minus sign and the first digit.
• --5 is not a valid integer (only one minus sign allowed)
• +5 is not a valid integer (plus sign is not allowed)

All variables should be declared as an integer. Variables must be declared before they are used. All variables are global (and static).

int <variable>.

Variable names are case sensitive and have a maximum length of 20 characters. Variable names start with a letter (alphabetical character) and continue with alphanumeric characters or an underscore character.

example: int myVar.

All variables are initialized with the value 0 at the time of creation.

move <int_value> to <variable>.
example: 
• move 25 to myVar. {assigns 25 to myVar}
• move myVar to yourVar. {assigns myVar to yourVar}

add <int_value> to <variable>.
Increments the variable by int_value.
example: 
• add 2 to sum . {The value of sum increases by 2}

sub <int_value> from <variable>.
example: 
• sub t from total. {The value of total decreases by t}

out <out_list>.

example: 
• out “The result is:”,sum.

An integer value is either a variable or a constant.

<int_value>→<variable>|<int_const>

An output list is a list of strings and integer values separated by commas.

<out_list>→<out_list>,<list_element>|<list_element>
<list_element>→<int_value>|<string>| newline

A string is any sequence of characters between two quotation marks. example: “Hello, this is a string!”

loop <int_value> times <line>

{OR}

loop <int_value> times <code_block>

A loop starts with the int_value and at each iteration decrements the value of int_value by one. If int_value is a variable, the value of the variable can be accessed and modified during the loop. After the loop the variable takes the value 0. The last iteration of the loop operates with the value 1.

example:

• loop 10 times out “*”. {writes 10 stars on the screen}

A code block is a list of code lines between square brackets. A code block can be used in a loop, interchangeably with a single line of code. By using code blocks, loops may be nested within each other.

example:

loop size times
[ out size, newline.
add size to sum.
]

Developed by @De3ph and @yasbas1 for project of Programming Languages course giving by Ege University/Turkey