.. index:: 
	single: Reference; Introduction

==================
Language Reference
==================

In this chapter we will learn about

* Language keywords
* Language Functions
* Compiler Errors
* Runtime Errors
* Environment Errors
* Language Grammar
* Virtual Machine (VM) Instructions

.. index:: 
	pair: Reference; Language Keywords

Language Keywords
=================

Keywords Count : 49

* again
* and
* but
* bye
* call
* case
* catch
* changeringkeyword
* changeringoperator
* class
* def
* do
* done
* else
* elseif
* end
* exit
* for
* from
* func
* get
* give
* if
* import
* in
* load
* loadsyntax
* loop
* new
* next
* not
* off
* ok
* on
* or
* other
* package
* private
* put
* return
* see
* step
* switch
* to
* try
* while
* endfunc
* endclass
* endpackage

.. index:: 
	pair: Reference; Language Functions

Language Functions
==================

Functions Count : 199

.. code-block:: ring

	len() add() del() sysget() clock() lower()
	upper() input() ascii() char() date() time()
	filename() getchar() system() random() timelist() adddays()
	diffdays() version() clockspersecond() prevfilename() swap() shutdown()
	isstring() isnumber() islist() type() isnull() isobject()
	hex() dec() number() string() str2hex() hex2str()
	str2list() list2str() str2hexcstyle() left() right() trim()
	copy() substr() lines() strcmp() eval() raise()
	assert() isalnum() isalpha() iscntrl() isdigit() isgraph()
	islower() isprint() ispunct() isspace() isupper() isxdigit()
	locals() globals() functions() cfunctions() islocal() isglobal()
	isfunction() iscfunction() packages() ispackage() classes() isclass()
	packageclasses() ispackageclass() classname() 
	objectid() attributes() methods()
	isattribute() ismethod() isprivateattribute() 
	isprivatemethod() addattribute() addmethod()
	getattribute() setattribute() mergemethods() 
	packagename() ringvm_fileslist() ringvm_calllist()
	ringvm_memorylist() ringvm_functionslist() 
	ringvm_classeslist() ringvm_packageslist() 
	ringvm_cfunctionslist() ringvm_settrace()
	ringvm_tracedata() ringvm_traceevent() ringvm_tracefunc() 
	ringvm_scopescount() ringvm_evalinscope() ringvm_passerror()
	ringvm_hideerrormsg() ringvm_callfunc() 
	list() find() min() max()
	insert() sort() reverse() binarysearch() sin() cos()
	tan() asin() acos() atan() atan2() sinh()
	cosh() tanh() exp() log() log10() ceil()
	floor() fabs() pow() sqrt() unsigned() decimals()
	murmur3hash() fopen() fclose() fflush() freopen() tempfile()
	tempname() fseek() ftell() rewind() fgetpos() fsetpos()
	clearerr() feof() ferror() perror() rename() remove()
	fgetc() fgets() fputc() fputs() ungetc() fread()
	fwrite() dir() read() write() fexists() int2bytes()
	float2bytes() double2bytes() bytes2int() 
	bytes2float() bytes2double() ismsdos()
	iswindows() iswindows64() isunix() 
	ismacosx() islinux() isfreebsd()
	isandroid() windowsnl() currentdir() 
	exefilename() chdir() exefolder()
	loadlib() closelib() callgc() varptr() 
	intvalue() object2pointer()
	pointer2object() nullpointer() space() 
	ptrcmp() ring_state_init() ring_state_runcode()
	ring_state_delete() ring_state_runfile() ring_state_findvar() 
	ring_state_newvar() ring_state_runobjectfile() ring_state_main()
	ring_state_setvar() 

.. index:: 
	pair: Reference; Compiler Errors

Compiler Errors
===============

* Error (C1)  : Error in parameters list, expected identifier
* Error (C2)  : Error in class name
* Error (C3)  : Unclosed control strucutre, 'ok' is missing
* Error (C4)  : Unclosed control strucutre, 'end' is missing
* Error (C5)  : Unclosed control strucutre, next is missing
* Error (C6)  : Error in function name
* Error (C7)  : Error in list items
* Error (C8)  : Parentheses ')' is missing 
* Error (C9)  : Brackets ']' is missing 
* Error (C10) : Error in parent class name
* Error (C11) : Error in expression operator
* Error (C12) : No class definition
* Error (C13) : Error in variable name
* Error (C14) : Try/Catch miss the Catch keyword!
* Error (C15) : Try/Catch miss the Done keyword!
* Error (C16) : Error in Switch statement expression!
* Error (C17) : Switch statement without OFF
* Error (C18) : Missing closing brace for the block opened!
* Error (C19) : Numeric Overflow!
* Error (C20) : Error in package name
* Error (C21) : Unclosed control strucutre, 'again' is missing
* Error (C22) : Function redefinition, function is already defined!
* Error (C23) : Using '(' after number!
* Error (C24) : The parent class name is identical to the subclass name
* Error (C25) : Trying to access the self reference after the object name"
* Error (C26) : Class redefinition, class is already defined!

.. index:: 
	pair: Reference; Runtime Errors

Runtime Errors
==============

* Error (R1)  : Cann't divide by zero !
* Error (R2)  : Array Access (Index out of range) !
* Error (R3)  : Calling Function without definition !
* Error (R4)  : Stack Overflow !
* Error (R5)  : Can't access the list item, Object is not list !
* Error (R6)  : Variable is required
* Error (R7)  : Can't assign to a string letter more than one character
* Error (R8)  : Variable is not a string 
* Error (R9)  : Using exit command outside loops 
* Error (R10) : Using exit command with number outside the range 
* Error (R11) : error in class name, class not found! 
* Error (R12) : error in property name, property not found! 
* Error (R13) : Object is required
* Error (R14) : Calling Method without definition !
* Error (R15) : error in parent class name, class not found! 
* Error (R16) : Using braces to access unknown object ! 
* Error (R17) : error, using 'Super' without parent class! 
* Error (R18) : Numeric Overflow! 
* Error (R19) : Calling function with less number of parameters!
* Error (R20) : Calling function with extra number of parameters!
* Error (R21) : Using operator with values of incorrect type
* Error (R22) : Using loop command outside loops 
* Error (R23) : Using loop command with number outside the range 
* Error (R24) : Using uninitialized variable 
* Error (R25) : Error in package name, Package not found! 
* Error (R26) : Calling private method from outside the class 
* Error (R27) : Using private attribute from outside the class 
* Error (R28) : Using bad data type as step value
* Error (R29) : Using bad data type in for loop
* Error (R30) : parent class name is identical to child class name 
* Error (R31) : Trying to destory the object using the self reference 
* Error (R32) : The CALL command expect a variable contains string!
* Error (R33) : Bad decimals number (correct range >= 0 and <=14) !
* Error (R34) : Variable is required for the assignment operation
* Error (R35) : Can't create/open the file!
* Error (R36) : The column number is not correct! It's greater than the number of columns in the list
* Error (R37) : Sorry, The command is not supported in this context
* Error (R38) : Runtime Error in loading the dynamic library!
* Error (R39) : Error occurred creating unique filename.

.. index:: 
	pair: Reference; Environment Errors

Environment Errors
==================

* Error (E1) : Caught SegFault
* Error (E2) : Out of Memory
* Error (E3) : Deleting scope while no scope!
* Error (E4) : Long VM Instruction!

.. index:: 
	pair: Reference; Language Grammar

Language Grammar
================

Program ---> {statement}

Statement ---> 'package' <Identifier> { '.' <Identifier> } ['{' {statement} '}'] ['end'|'endpackage']

Statement ---> 'class' <Identifier> [ 'from'|':'|'<' <Identifier> ] ['{' {statement} '}']['end'|'endclass']

Statement ---> 'func'|'def' <Identifier> [ParaList] ['{' {statement} '}']['end'|'endfunc']

Statement ---> 'import' <Identifier> { '.' <Identifier> }

Statement ---> 'private'

Statement ---> 'load' ['package'] <Literal>

Statement ---> 'loadsyntax' <Literal>

Statement ---> 'changeringkeyword' <OldKeyword> <NewKeyword>

Statement ---> 'changeringoperator' <OldOperator> <NewOperator>

Statement ---> 'see'|'put' <Expr>

Statement ---> 'give'|'get' <Identifier>

Statement ---> 'if' <Expr> ['{'] {statement} [ {'but'|'elseif' <Expr> {Statement} } ] ['else' {Statement} ] 'ok'|'end'|'}'

Statement ---> 'Switch' <Expr> ['{'] { 'on'|'case' <Expr> {statement} } ['other' {Statement} ]  'off'|'end'|'}'

Statement ---> 'for' <Identifier> '=' <Expr> 'to' <Expr> [ 'step' <Expr> ] ['{'] {Statement} 'next'|'end'|'}'

Statement ---> 'for' <Identifier> 'in' <Expr>  [ 'step' <Expr> ] ['{'] {statement} 'next'|'end'|'}'

Statement ---> 'while' <Expr> ['{'] {statement} 'end'|'}'

Statement ---> 'do' {statement} 'again' <Expr> 

Statement ---> 'try' {statement} ['{'] 'catch' {statement} 'done'|'end'|'}'

Statement ---> 'return' <Expr>

Statement ---> 'bye'

Statement ---> 'exit'

Statement ---> 'loop'

Statement ---> <Expr>

Statement ---> epslion

ParaList ---> epslion

ParaList ---> ['('] <Identifier> [{ ',' <Identifier> }] [')']

Expr ---> <LogicNot> [{ 'and'|'or' <LogicNot> }]

LogicNot --> ['not'] <EqualOrNot> 

EqualOrNot --> [ '='|'!=' ] <Compare>

Compare ---> <BitOrXor> [ { '<' | '>' | '<=' | '>=' <BitOrXor> } ]

BitOrXor ---> <BitAnd> [ { '|' | '^' <BitAnd> } ]

BitAnd ---> <BitShift> [ { '&' <BitShift> } ]

BitShift ---> <Arithmetic> [ { '<<' | '>>' <Arithmetic> } ]

Arithmetic ---> <Term> [ { '+' | '-'  <Term>  } ]

Term ---> <Range> [ { '*' | '/' | '%' <Range> } ]

Range ---> <Factor> [ ':' <Factor> ]

Factor ---> <Identifier> [ {Mixer} ] [ '=' <Expr> ]

Factor ---> <Number>

Factor ---> <Literal>

Factor ---> ':' <Identifier>

Factor ---> '-' <Expr>

Factor ---> '(' <Expr> ')'

Factor ---> <List>

Factor ---> 'new' <Identifier>

Factor ---> <AnonymousFunction>

Factor ---> 'call' <identifier> { '.' <Identifier> } '(' <Parameters> ')'

List ---> '[' [ <Expr> { ',' <Expr> } ] ']'

Mixer ---> { '.' <Identifier> }

Mixer ---> '[' <Expr> ']'

Mixer ---> '(' [ <Expr> [ { ',' <Expr> }] ]  ')'

Mixer ---> '{' {Statement} '}'

AnonymousFunction ---> 'func'|'def'| [<ParaList>] '{' {Statement} '}'

.. index:: 
	pair: Reference; Virtual Machine Instructions

Virtual Machine (VM) Instructions
=================================

Definitions :-

* VM : Virtual Machine
* Stack : VM Stack
* IR : Instruction Register
* PC : Program Counter
* VP : Variable Pointer
* Stack[nSize] : Last Item in the Stack (Last In - First Out)
* VV : Variable Value (We have a Pointer to a variable, And we access this variable value)
(Stack and Variables)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_PUSHC 		Add string from the IR to the stack
* ICO_PUSHN 		Add number from the IR to the stack
* ICO_PUSHV 		Replace VP in the stack[nSize] with the variable value 
* ICO_LOADADDRESS 	Read variable name from the IR, push VP to the stack
* ICO_ASSIGNMENT 	Stack[nSize-1] VV = Stack[nSize] VV , POP Stack[nSize]
* ICO_INC 		Increment Number in Stack[nSize] by 1
* ICO_LOADAPUSHV	The same as ICO_LOADADDRESS then ICO_PUSHV
* ICO_NEWLINE		Store new line number (debug info)
* ICO_FREESTACK		Remove all items from the stack , nSize = 0
* ICO_FILENAME		Store the source code file name (debug info)
* ICO_FREELOADASCOPE	Free the Scope List of the current Expression
=======================	============================================================================

(Jump)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_JUMP		Set PC to new value from the IR 
* ICO_JUMPZERO		If Stack[nSize] is a number = 0 then Set PC to new value from the IR 
* ICO_JUMPFOR		End of for loop
* ICO_JUMPONE		If Stack[nSize] is a number = 1 then Set PC to new value from the IR 
* ICO_JUMPZERO2		As ICO_JUMPZERO but add 1 to the stack (required for many 'AND' conditions)
* ICO_JUMPONE2		As ICO_JUMPONE but add 1 to the stack (required for many 'OR' conditions)
=======================	============================================================================

(Compare)

=======================	==========================================================================================================
Operation			Description
=======================	==========================================================================================================
* ICO_LESSEQUAL		If stack[nSize-1] <= stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
* ICO_EQUAL		If stack[nSize-1] = stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
* ICO_LESS		If stack[nSize-1] < stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
* ICO_GREATER		If stack[nSize-1] > stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
* ICO_GREATEREQUAL	If stack[nSize-1] >= stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
* ICO_NOTEQUAL		If stack[nSize-1] != stack[nSize] , POP stack[nSize], set Stack[nSize-1] = 1 else set Stack[nSize-1] = 0
=======================	==========================================================================================================

(Math)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_SUM		Stack[nSize-1] = Stack[nSize-1] + Stack[nSize] , POP stack[nSize]
* ICO_SUB		Stack[nSize-1] = Stack[nSize-1] - Stack[nSize] , POP stack[nSize]
* ICO_MUL		Stack[nSize-1] = Stack[nSize-1] * Stack[nSize] , POP stack[nSize]
* ICO_DIV		Stack[nSize-1] = Stack[nSize-1] / Stack[nSize] , POP stack[nSize]
* ICO_MOD		Stack[nSize-1] = Stack[nSize-1] % Stack[nSize] , POP stack[nSize]
* ICO_NEG		Stack[nSize] = - Stack[nSize-1]
* ICO_PLUSPLUS		Stack[nSize] = Stack[nSize] + 1
* ICO_MINUSMINUS	Stack[nSize] = Stack[nSize] - 1
=======================	============================================================================

(Logic)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_AND		Stack[nSize-1] = Stack[nSize-1] && Stack[nSize] , POP stack[nSize]
* ICO_OR		Stack[nSize-1] = Stack[nSize-1] || Stack[nSize] , POP stack[nSize]
* ICO_NOT		Stack[nSize]   = ! Stack[nSize]  
=======================	============================================================================

(Lists)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_LISTSTART		Start New List in Temp. Memory
* ICO_LISTITEM		Add List Item
* ICO_LISTEND		End List
* ICO_LOADINDEXADDRESS	Stack[nSize-1] = Stack[nSize-1] VV [ Stack[nSize] ] , POP stack[nSize]
=======================	============================================================================

(Functions)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_LOADFUNC		Find function
* ICO_CALL		Call function
* ICO_RETURN		Return from function
* ICO_RETNULL		Return NULl from function
* ICO_RETFROMEVAL	Return after eval() 
* ICO_RETITEMREF	Return the list item reference - not the value
* ICO_NEWFUNC		Start new function
* ICO_BLOCKFLAG		Flag to determine where to jump later (after ICO_RETURN)
* ICO_FUNCEXE		Start executing function
* ICO_ENDFUNCEXE	End function execution
* ICO_ANONYMOUS		Anonymous function
=======================	============================================================================

(User Interface)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_PRINT		Print value to the standard output
* ICO_GIVE		Get input from the keyboard
=======================	============================================================================

(End Program/Loop)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_BYE		End execution of VM
* ICO_EXITMARK		Place to exit to from a loop	
* ICO_POPEXITMARK	Remove exit mark
* ICO_EXIT		Break from one loop or more 
* ICO_LOOP		Continue to next loop 
=======================	============================================================================

(For Better Performance)

========================	============================================================================
Operation			Description
========================	============================================================================
* ICO_PUSHP			Push pointer to the stack
* ICO_INCP			Increment variable value using pointer
* ICO_PUSHPV			Push value of variable using variable pointer
* ICO_INCJUMP			Increment then jump
* ICO_INCPJUMP			Increment using pointer then jump
* ICO_JUMPVARLENUM		Jump if variable value is <= numeric value
* ICO_JUMPVARPLENUM		Jump if variable value (using pointer) <= numeric value 
* ICO_LOADFUNCP			Push function pointer
* ICO_PUSHPLOCAL		Push pointer to local variable
* ICO_INCLPJUMP			Increment value using pointer to local variable then jump
* ICO_JUMPVARLPLENUM		Jump if the variable value (using pointer) <= numeric value
* ICO_INCPJUMPSTEP1	 	Increment value using variable pointer then jump (for loop step = 1)
* ICO_JUMPVARPLENUMSTEP1	Increment value using variable pointer then jump (for loop step = 1)
========================	============================================================================

(Try-Catch-Done)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_TRY		Start try region
* ICO_DONE		End try region
=======================	============================================================================

(Duplicate and Range)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_DUPLICATE		Duplicate stack value
* ICO_RANGE		Create list from value to value
=======================	============================================================================

(OOP)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_NEWOBJ		Create new object, get class name from the IR, push object pointer to the stack.
* ICO_SETSCOPE		Called after creating new object, set the active scope to be the object scope.
* ICO_LOADSUBADDRESS	Get object attribute, push the pointer to the stack.
* ICO_LOADMETHOD	Find object method 
* ICO_AFTERCALLMETHOD	Used after calling a method - normal case
* ICO_AFTERCALLMETHOD2  Used after calling a method - second case
* ICO_NEWCLASS		Start new class region
* ICO_BRACESTART	Open brace
* ICO_BRACEEND		End brace
* ICO_IMPORT		Import package
* ICO_PRIVATE		start private attributes region
* ICO_SETPROPERTY	set attribute value - check for setter.	
* ICO_CALLCLASSINIT	call call init() method.
=======================	============================================================================

(Other)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_SETREFERENCE	Copy by reference
* ICO_KILLREFERENCE	Remove reference
* ICO_ASSIGNMENTPOINTER Determine the left side variable
* ICO_BEFOREEQUAL	Determine operators like += , -= , ... etc
=======================	============================================================================

(Bitwise Operators)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_BITAND		Stack[nSize-1] = Stack[nSize-1] & Stack[nSize] , POP stack[nSize]
* ICO_BITOR		Stack[nSize-1] = Stack[nSize-1] | Stack[nSize] , POP stack[nSize]
* ICO_BITXOR		Stack[nSize-1] = Stack[nSize-1] ^ Stack[nSize] , POP stack[nSize]
* ICO_BITNOT		Stack[nSize] = ! Stack[nSize] 
* ICO_BITSHL		Stack[nSize-1] = Stack[nSize-1] << Stack[nSize] , POP stack[nSize]
* ICO_BITSHR		Stack[nSize-1] = Stack[nSize-1] >> Stack[nSize] , POP stack[nSize]
=======================	============================================================================

(For Step)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_STEPNUMBER	Determine step number in for loop
* ICO_POPSTEP		POP step number from steps stack
* ICO_LOADAFIRST	Load the first address of variable name 
=======================	============================================================================

(Custom Global Scope)

=======================	============================================================================
Operation			Description
=======================	============================================================================
* ICO_NEWGLOBALSCOPE	Start new custom global scope - used by 'load package' command
* ICO_ENDGLOBALSCOPE	End of custom global scope - used by 'load package' command
* ICO_SETGLOBALSCOPE	Set the current global scope 
=======================	============================================================================

