Low Level Functions

In this chapter we will learn about the low level functions provided by Ring

It’s not recommended to use these functions in your application code

These functions exist for C/C++ developers who are developing Ring libraries/tools

We expect from those developers to know about pointers and dynamic memory management

* callgarbagecollector()| callgc() * variablepointer() | varptr() * space() * nullpointer() | nullptr() * object2pointer() | obj2ptr() * pointer2object() | ptr2obj() * ispointer() * pointercompare() | ptrcmp() * setpointer() | setptr() * getpointer() | getptr() * pointer2string() | ptr2str() * memorycopy() | memcpy() * ringvm_cfunctionslist() * ringvm_functionslist() * ringvm_classeslist() * ringvm_packageslist() * ringvm_memorylist() * ringvm_calllist() * ringvm_fileslist() * ringvm_settrace() * ringvm_tracedata() * ringvm_traceevent() * ringvm_tracefunc() * ringvm_scopescount() * ringvm_evalinscope() * ringvm_passerror() * ringvm_hideerrorMsg() * ringvm_callfunc() * ringvm_see() * ringvm_give() * ringvm_info() * ringvm_ismempool() * ringvm_codelist() 

callgc() function

Syntax:

callgc() # Short name callgarbagecollector() # Long name 

Use this function to force calling the garbage collector during function execution when you use a loop that create temp. variables that you don’t free using the assignment operation.

It’s very rare to need this function but it’s useful when you create something like event-loop for your game engine and start creating lists on the fly when you call functions.

Example

While True # process events # call functions using temp. lists like myfunc(["temp list"]) # call the garbage collector callgc() End 

Tip

In Ring the garbage collector works automatically in the end of function execution or when you use the assignment statement.

varptr() function

Use the varptr() function when you need to pass a pointer to a C/C++ function.

Syntax:

varptr(cVariableName,cPointerType) ---> Low Level Object (C Pointer) variablepointer(cVariableName,cPointerType) ---> Low Level Object (C Pointer) 

example:

r = 10 z = 20 see r + nl see varptr("r","int") see varptr("z","int") 

Output:

10 00E3C740 int 2 00E3BEC0 int 2 

Note

the low level object is a list contains three items (The Pointer, The Type, The Status)

space() function

Use the space function to allocate a specific number of bytes in Memory.

Syntax:

Space(nBytesCount) ---> String 

Example:

mystring = space(200) See "String Size : " + len(mystring) + nl See "String : " + mystring + nl See "String Pointer : " See varptr("mystring",:char) 

Output:

String Size : 200 String : String Pointer : 00FF8FE8 char 2 

Note

You may need the space() and VarPtr() functions to pass buffers to C functions.

Tip

To free the memory allocated using the space() function, use the Assignment operator

mystring = space(1000) # Allocate memory (1000 bytes) mystring = NULL # Free memory stored in mystring 

Note

We don’t need to free the memory if it’s a local variable that will be deleted after the function execution.

nullpointer() function

Syntax:

nullptr() # Short name nullpointer() # Long name 

You may need to pass the NULL pointer to a C function that may expect a pointer as parameter and accept NULL pointers for optional parameters.

Example:

The next example uses the SDL_BlitSurface() function from the LibSDL Library through RingSDL The function accept SDL_Rect pointers in the second and the last parameter. Also the function accept NULL pointers, so we can pass them using the NULLPointer() Function.

SDL_BlitSurface(text, nullpointer(), surface, nullpointer()) 

Note

The previous code doesn’t work alone, you need to learn how to use RingSDL first.

Tip

We can pass NULL as parameter instead of using the NULLPointer() function

SDL_BlitSurface(text, NULL, surface, NULL) 

object2pointer() function

Use this function to get a C pointer for Ring lists and objects

Syntax:

obj2ptr(List|Object) --> Low Level Object ( C Pointer ) # Short name object2pointer(List|Object) --> Low Level Object ( C Pointer ) # Long name 

Note

You have to be sure that the Pointer still valid (Doesn’t point to deallocated memory)

pointer2object() function

Use this function to get the Ring list and/or object from the low level object (C Pointer)

Syntax:

ptr2obj(Low Level Object) ---> ListReference|ObjectReference # Short name pointer2object(Low Level Object) ---> ListReference|ObjectReference # Long name 

Note

Before using Pointer2Object() to create a reference, Be sure that the Pointer is valid (Doesn’t point to deallocated memory, i.e. deleted list/object)

Tip

After using Pointer2Object() to create a reference, and if the original List/Object is deleted, Ring will uses reference counting and will keep the List/Object until the latest reference is removed

Example:

# Create the list mylist = 1:5 # Create pointer to the list x = object2pointer(mylist) see x see nl # Add items to the list mylist + "welcome" # Get a copy from the list y = pointer2object(x) # print the new list items see y 

Output:

0069A5D8 OBJECTPOINTER 0 1 2 3 4 5 welcome 

Note

In Ring the assignment operator copy lists and objects by value, to copy lists and objects by reference Just use the object2pointer() and pointer2object() functions.

The functions Object2Pointer() and Pointer2Object() are low level functions

We have to be careful when using them to avoid memory problems

If we created a Pointer to a (Local Variable)

This local variable will be deleted from the memory after the end of the function/method execution

This means that the pointer created with Object2Pointer() will becomes a dangling pointer

i.e. A pointer that points to the memory location of the deallocated memory

Using this invalid pointer could lead to (CRASH or Memory Corruption).

If you will use pointers (Using Object2Pointer() or Pointer2Object()) then never use pointers that point to the memory that are deallocated.

In simple words, Keep the memory (Don’t delete it if you still need it)

i.e. instead of using (Local Variables) that will be deleted, You can use Class Attributes or Global Variables.

ispointer() function

Check if the parameter is a pointer (C Object) or not.

Syntax:

IsPointer(vPara) ---> True|False # Long name 

Example :

fp = fopen(filename(),"r") ? type(fp) ? ispointer(fp) 

Output :

file 1 

ptrcmp() function

We can compare between two pointers (C Objects) using the ptrcmp() function.

Syntax:

ptrcmp(oObject1,oObject2) ---> value = 1 if oObject1 = oObject2 value = 0 if oObject1 != oObject2 pointercompare(oObject1,oObject2) ---> value = 1 if oObject1 = oObject2 value = 0 if oObject1 != oObject2 

Example:

fp = fopen("ptrcmp.ring","r") fp2 = fp fp3 = fopen("ptrcmp.ring","r") see ptrcmp(fp,fp2) + nl see ptrcmp(fp,fp3) + nl fclose(fp) fclose(fp3) 

Output:

1 0 

setpointer() function

Set the pointer address to another address

Syntax:

setptr(pointer,nNewAddress) # Short name setpointer(pointer,nNewAddress) # Long name 

Note

Using setPointer() and getPointer() functions we can change the Memory Address

getpointer() function

Get the pointer address

Syntax:

getptr(pointer) ---> nAddress # Short name getpointer(pointer) ---> nAddress # Long name 

Example:

? "Sample about using setPointer() and getPointer() functions" ? copy("=",50) pointer = NULLPOINTER() ? pointer ? "Type: " + type(pointer) ? "Address: " + Upper(hex(getpointer(pointer))) ? copy("=",50) name = "ring" pointer = varptr(:name,:char) ? pointer ? "Type: " + type(pointer) ? "Address: " + Upper(hex(getpointer(pointer))) ? copy("=",50) setpointer(pointer, getpointer(pointer) + 1 ) ? "After Update" ? "Address: " + Upper(hex(getpointer(pointer))) ? copy("=",50) 

Output:

================================================== 00000000 NULLPOINTER 0 Type: NULLPOINTER Address: 0 ================================================== 026E2BA8 char 0 Type: char Address: 26E2BA8 ================================================== After Update Address: 26E2BA9 ================================================== 

pointer2string() function

Convert a pointer to a string of binary data

If you want to convert the string to a pointer again use VarPtr() function

Syntax:

ptr2str(pointer,nStart,nCount) ---> cString # Short name pointer2string(pointer,nStart,nCount) ---> cString # Long name 

Note

pointer2String() return another copy of the data

Note

if nStart is Zero, this means starting from the first character

Example:

name = "ring" pointer = varptr(:name,:char) ? pointer ? "Type: " + type(pointer) ? "Address: " + Upper(hex(getpointer(pointer))) ? "Get 4 bytes starting from the pointer address" mystring = Pointer2String(pointer,0,4) ? mystring ? "Get 2 bytes starting from the pointer address + 1" mystring2 = Pointer2String(pointer,1,2) ? mystring2 

Output:

01E03380 char 0 Type: char Address: 1E03380 Get 4 bytes starting from the pointer address ring Get 2 bytes starting from the pointer address + 1 in 

memcpy() function

Syntax:

memcpy(pDestinationPointer,cSourceString,nSize) # Short name memorycopy(pDestinationPointer,cSourceString,nSize) # Long name 

Example:

str = space(9) pointer = varptr(:str,"char") memcpy(pointer,"one",3) ? str setPointer(pointer,getPointer(pointer)+3) memcpy(pointer,"one",3) ? str setPointer(pointer,getPointer(pointer)+3) memcpy(pointer,"one",3) ? str 

Output:

one oneone oneoneone 

ringvm_cfunctionslist() function

The Function return a list of functions written in C.

Syntax:

RingVM_CFunctionsList() ---> List 

Example:

See RingVM_CFunctionsList() 

ringvm_functionslist() function

The Function return a list of functions written in Ring.

Each List Member is a list contains the next items

  • Function Name

  • Program Counter (PC) - Function Position in Byte Code.

  • Source Code File Name

  • Private Flag (For Private Methods in Classes)

Syntax:

RingVM_FunctionsList() ---> List 

Example:

test() func test see ringvm_functionslist() 

Output:

test 8 B:/ring/tests/scripts/functionslist.ring 0 

ringvm_classeslist() function

The Function return a list of Classes.

Each List Member is a list contains the next items

  • Class Name

  • Program Counter (PC) - Class Position in Byte Code.

  • Parent Class Name

  • Methods List

  • Flag (Is parent class information collected)

  • Pointer to the package (or NULL if no package is used)

Syntax:

RingVM_ClassesList() ---> List 

Example:

see ringvm_classeslist() class class1 func f1 class class2 from class1 class class3 from class1 

Output:

class1 9 f1 13 B:/ring/tests/scripts/classeslist.ring 0 0 00000000 class2 16 class1 0 00000000 class3 20 class1 0 00000000 

ringvm_packageslist() function

The Function return a list of Packages.

Each List Member is a list contains the next items

  • Package Name

  • Classes List

Syntax:

RingVM_PackagesList() ---> List 

Example:

see ringvm_packageslist() package package1 class class1 package package2 class class1 package package3 class class1 

Output:

package1 class1 11 0 00FEF838 package2 class1 17 0 00FEF978 package3 class1 23 0 00FEFF68 

ringvm_memorylist() function

The Function return a list of Memory Scopes and Variables.

Each List Member is a list contains variables in a different scope.

Each Item in the scope list is a list contains the next items

  • Variable Name

  • Variable Type

  • Variable Value

  • Pointer Type (List/Item) if the value is a list

  • Private Flag (if the variable is an attribute in a Class)

Syntax:

RingVM_MemoryList() ---> List 

Example:

x = 10 test() func test y = 20 see ringvm_memorylist() 

Output:

true 2 1 0 0 false 2 0 0 0 nl 1 0 0 null 1 0 0 ring_gettemp_var 4 00000000 0 0 ccatcherror 1 NULL 0 0 ring_settemp_var 4 00000000 0 0 ring_tempflag_var 2 0 0 0 stdin 3 50512DB8 file 0 0 0 stdout 3 50512DD8 file 0 0 0 stderr 3 50512DF8 file 0 0 0 this 4 00000000 0 0 sysargv 3 B:\ring\bin/ring B:/ring/tests/scripts/memorylist.ring 0 0 x 2 10 0 0 y 2 20 0 0 

ringvm_calllist() function

The Function return a list of the functions call list.

Each List Member is a list contains the next items

  • Function Type

  • Function Name

  • Program Counter (PC)

  • Stack Pointer (SP)

  • Method or Function Flag

  • Caller PC

  • Caller Line Number

  • Parameters Count

Syntax:

RingVM_CallList() ---> List 

Example:

hello() func hello test() func test mylist = ringvm_calllist() for t in mylist see t[2] + nl next 

Output:

hello test ringvm_calllist 

ringvm_fileslist() function

Function return a list of the Ring Files.

Syntax:

RingVM_FilesList() ---> List 

Example:

load "stdlib.ring" see ringvm_fileslist() 

Output:

B:/ring/tests/scripts/fileslist.ring B:\ring\bin\stdlib.ring eval stdlib.ring stdlib.rh stdclasses.ring stdfunctions.ring stdbase.ring stdstring.ring stdlist.ring stdstack.ring stdqueue.ring stdmath.ring stddatetime.ring stdfile.ring stdsystem.ring stddebug.ring stddatatype.ring stdconversion.ring stdodbc.ring stdmysql.ring stdsecurity.ring stdinternet.ring stdhashtable.ring stdtree.ring 

ringvm_settrace()

The function ringvm_settrace() determine the Trace function name

The trace function is a Ring function that will be called for each event

Syntax:

RingVM_SetTrace(cCode) 

ringvm_tracedata()

Inside the function that we will use for tracing events

We can use the ringvm_tracedata() function to get the event data.

The event data is a list contains the next items

  • The Source Code Line Number

  • The Source File Name

  • The Function/Method Name

  • Method or Function (Bool : True=Method, False=Function/File)

Syntax:

RingVM_TraceData() ---> aDataList 

ringvm_traceevent()

Inside the function that we will use for tracing events

We can use ringvm_traceevent() to know the event type

  • New Line

  • Before Function

  • After Function

  • Runtime Error

  • Before C Function

  • After C Function

Syntax:

RingVM_TraceEvent() ---> nTraceEvent 

ringvm_tracefunc()

The function return the name of the function that we are using for tracing events.

Syntax:

RingVM_TraceEvent() ---> cCode 

ringvm_scopescount()

We can use the RingVM_ScopesCount() function to know the number of scopes used in the application.

In the start of the program, We have the (global scope only)

When we call a function, A new scope is created.

When the function execution is done, the function scope is deleted.

Syntax:

RingVM_ScopesCount() ---> nScopes 

ringvm_evalinscope()

The function ringvm_evalinscope() is similar to the eval() function

Unlike eval() which execute the code in the current scope

Using RingVM_EvalInScope() we can execute the code in a specific scope.

Syntax:

RingVM_EvalInScope(nScope,cCode) 

ringvm_passerror()

When we have runtime error, After printing the Error message, Ring will end the execution of the program.

Using ringvm_passerror() we can avoid that, and continue the execution of our program.

Syntax:

RingVM_PassError() 

ringvm_hideerrormsg()

We can disable/enable displaying the runtime error messages using the RingVM_HideErrorMsg() function.

Syntax:

RingVM_HideErrorMsg(lStatus) 

ringvm_callfunc()

We can call a function from a string without using eval() using the ringvm_callfunc()

Syntax:

RingVM_CallFunc(cFuncName) 

Example - Using the Trace Functions

The next example use the Trace Functions to trace the program Events!

In practical, We will use the Trace Library instead of these low level functions!

load "tracelib.ring" ringvm_settrace("mytrace()") see "Hello, world!" + nl see "Welcome" + nl see "How are you?" +nl mytest() new myclass { mymethod() } func mytest see "Message from mytest" + nl func mytrace see "====== The Trace function is Active ======" + nl + "Trace Function Name : " + ringvm_TraceFunc() + nl + "Trace Event : " switch ringvm_TraceEvent() on TRACEEVENT_NEWLINE see "New Line" on TRACEEVENT_NEWFUNC see "New Function" on TRACEEVENT_RETURN see "Return" on TRACEEVENT_ERROR see "Error" on TRACEEVENT_BEFORECFUNC see "Before C Function" on TRACEEVENT_AFTERCFUNC see "After C Function" off see nl + "Line Number : " + ringvm_tracedata()[TRACEDATA_LINENUMBER] + nl + "File Name : " + ringvm_tracedata()[TRACEDATA_FILENAME] + nl + "Function Name : " + ringvm_tracedata()[TRACEDATA_FUNCNAME] + nl + "Method or Function : " if ringvm_tracedata()[TRACEDATA_METHODORFUNC] = TRACEDATA_METHODORFUNC_METHOD see "Method" else if ringvm_tracedata()[TRACEDATA_FUNCNAME] = NULL see "Command" else see "Function" ok ok see nl + Copy("=",42) + nl class myclass func mymethod see "Message from mymethod" + nl 

Output:

====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : After C Function Line Number : 3 File Name : test1.ring Function Name : ringvm_settrace Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 5 File Name : test1.ring Function Name : Method or Function : Command ========================================== Hello, world! ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 6 File Name : test1.ring Function Name : Method or Function : Command ========================================== Welcome ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 7 File Name : test1.ring Function Name : Method or Function : Command ========================================== How are you? ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 8 File Name : test1.ring Function Name : Method or Function : Command ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Function Line Number : 8 File Name : test1.ring Function Name : mytest Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 12 File Name : test1.ring Function Name : mytest Method or Function : Function ========================================== Message from mytest ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 14 File Name : test1.ring Function Name : mytest Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : Return Line Number : 8 File Name : test1.ring Function Name : Method or Function : Command ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 9 File Name : test1.ring Function Name : Method or Function : Command ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 43 File Name : test1.ring Function Name : Method or Function : Command ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : Before C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : After C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Function Line Number : 9 File Name : test1.ring Function Name : mymethod Method or Function : Method ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 44 File Name : test1.ring Function Name : mymethod Method or Function : Method ========================================== Message from mymethod ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : Return Line Number : 9 File Name : test1.ring Function Name : Method or Function : Command ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : Before C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : After C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : Before C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : After C Function Line Number : 9 File Name : test1.ring Function Name : ismethod Method or Function : Function ========================================== ====== The Trace function is Active ====== Trace Function Name : mytrace() Trace Event : New Line Line Number : 11 File Name : test1.ring Function Name : Method or Function : Command ========================================== 

Example - The Trace Library

The next example uses the Trace functions provided by the Ring language to create the Trace library.

Using the Trace library we have nice Tracing tools and Interaction debugger too.

# Trace Events TRACEEVENT_NEWLINE = 1 TRACEEVENT_NEWFUNC = 2 TRACEEVENT_RETURN = 3 TRACEEVENT_ERROR = 4 TRACEEVENT_BEFORECFUNC = 5 TRACEEVENT_AFTERCFUNC = 6 # Trace Data TRACEDATA_LINENUMBER = 1 TRACEDATA_FILENAME = 2 TRACEDATA_FUNCNAME = 3 TRACEDATA_METHODORFUNC = 4 # Method of Function TRACEDATA_METHODORFUNC_METHOD = TRUE TRACEDATA_METHODORFUNC_NOTMETHOD = FALSE TRACE_BREAKPOINTS = TRUE TRACE_TEMPLIST = [] func Trace cType switch trim(lower(cType)) on :AllEvents ringvm_settrace("TraceLib_AllEvents()") on :Functions ringvm_settrace("TraceLib_Functions()") on :PassError ringvm_settrace("TraceLib_PassError()") on :Debugger ringvm_settrace("TraceLib_Debugger()") on :LineByLine ringvm_settrace("TraceLib_LineByLine()") off func TraceLib_AllEvents if right(ringvm_tracedata()[TRACEDATA_FILENAME],13) = "tracelib.ring" return ok see "====== The Trace function is Active ======" + nl + "Trace Function Name : " + ringvm_TraceFunc() + nl + "Trace Event : " switch ringvm_TraceEvent() on TRACEEVENT_NEWLINE see "New Line" on TRACEEVENT_NEWFUNC see "New Function" on TRACEEVENT_RETURN see "Return" on TRACEEVENT_ERROR see "Error" on TRACEEVENT_BEFORECFUNC see "Before C Function" on TRACEEVENT_AFTERCFUNC see "After C Function" off see nl + "Line Number : " + ringvm_tracedata()[TRACEDATA_LINENUMBER] + nl + "File Name : " + ringvm_tracedata()[TRACEDATA_FILENAME] + nl + "Function Name : " + ringvm_tracedata()[TRACEDATA_FUNCNAME] + nl + "Method or Function : " if ringvm_tracedata()[TRACEDATA_METHODORFUNC] = TRACEDATA_METHODORFUNC_METHOD see "Method" else if ringvm_tracedata()[TRACEDATA_FUNCNAME] = NULL see "Command" else see "Function" ok ok see nl + Copy("=",42) + nl func TraceLib_Functions if right(ringvm_tracedata()[TRACEDATA_FILENAME],13) = "tracelib.ring" return ok switch ringvm_TraceEvent() on TRACEEVENT_NEWFUNC see "Open Func : " + ringvm_TraceData()[TRACEDATA_FUNCNAME] + nl on TRACEEVENT_RETURN see "Return to Func : " + ringvm_TraceData()[TRACEDATA_FUNCNAME] + nl off func TraceLib_PassError if right(ringvm_tracedata()[TRACEDATA_FILENAME],13) = "tracelib.ring" return ok switch ringvm_TraceEvent() on TRACEEVENT_ERROR see nl see "TraceLib : After Error !" + nl ringvm_passerror() off func TraceLib_Debugger if right(ringvm_tracedata()[TRACEDATA_FILENAME],13) = "tracelib.ring" return ok switch ringvm_TraceEvent() on TRACEEVENT_ERROR _BreakPoint() off func TraceLib_LineByLine if right(ringvm_tracedata()[TRACEDATA_FILENAME],13) = "tracelib.ring" or ringvm_TraceEvent() != TRACEEVENT_NEWLINE return ok aList = ringvm_tracedata() see "Before Line : " + aList[TRACEDATA_LINENUMBER] + nl _BreakPoint() func BreakPoint if not TRACE_BREAKPOINTS return ok _BreakPoint() func _BreakPoint see nl+nl+Copy("=",60) + nl + Copy(" ",20)+"Interactive Debugger" + nl + Copy("=",60) + nl + "Command (Exit) : End Program" + nl + "Command (Cont) : Continue Execution" + nl + "Command (Locals) : Print local variables names" + nl + "Command (LocalsData) : Print local variables data" + nl + "Command (Globals) : Print global variables names" + nl + "We can execute Ring code" + nl + Copy("=",60) + nl while true see nl + "code:> " give cCode cmd = trim(lower(cCode)) if cmd = "exit" or cmd = "bye" shutdown() ok nScope = ringvm_scopescount()-2 switch cmd on "locals" ringvm_EvalInScope(nScope,"see locals() callgc()") loop on "localsdata" PrintLocalsData(nScope) loop on "globals" ringvm_EvalInScope(nScope,"see globals() callgc()") loop on "cont" ringvm_passerror() exit off Try ringvm_EvalInScope(nScope,cCode) catch see cCatchError done end func NoBreakPoints TRACE_BREAKPOINTS = FALSE func PrintLocalsData nScope if nScope = 1 # Global ringvm_Evalinscope(nScope,'TRACE_TEMPLIST = globals()') else ringvm_Evalinscope(nScope,'TRACE_TEMPLIST = locals() callgc()') ok see nl aTempList = TRACE_TEMPLIST TRACE_TEMPLIST = [] nSpaces = 5 for TRACE_ITEM in aTempList if len(TRACE_ITEM) + 5 > nSpaces nSpaces = len(TRACE_ITEM) + 5 ok next for TRACE_ITEM in aTempList see "Variable : " + TRACE_ITEM cVarName = TRACE_ITEM see copy(" ",nSpaces-len(cVarName)) + " Type : " ringvm_Evalinscope(nScope,"see type(" + TRACE_ITEM +")") ringvm_Evalinscope(nScope,"see Copy(' ',fabs(15-len(type(" + TRACE_ITEM +"))))") see " Value : " ringvm_Evalinscope(nScope,"see " + TRACE_ITEM) see nl next 

ringvm_see() function

Using the ringvm_see() function we can redefine the behavior of the See command

Also we can use ring_see() to have the original behavior

Example:

see "Hello world" + nl see 123 + nl see ["one","two","three"] see new point {x=10 y=20 z=30} func ringvm_see t ring_see("We want to print: ") ring_See(t) class point x y z 

Output:

We want to print: Hello world We want to print: 123 We want to print: one two three We want to print: x: 10.000000 y: 20.000000 z: 30.000000 

ringvm_give() function

Using the ringvm_give() function we can redefine the behavior of the Give command

Example:

see "Name: " give name see "Hello " + name func ringvm_give see "Mahmoud" + nl return "Mahmoud" 

Output:

Name: Mahmoud Hello Mahmoud 

ringvm_codelist() function

The Function return a list contains the Byte Code of the current program.

Each item is a sub list that represent an instruction

This sub list starts with the operation code (A Number) then the parameters

ringvm_info() function

The ringvm_info() is an internal function that return a list of information about the Ring VM structure.

It’s used only by the Ring Team in advanced tests to check the VM status.

Syntax:

ringvm_info() ---> List of information about the VM structure 

ringvm_ismempool() function

Check if we still have items in the memory pool or not

This function is used to write tests that could detect a memory leak

Syntax:

ringvm_ismempool() ---> lStatus 

ringvm_runcode() function

Similar to the Eval() function

1 - Used for GUI events like RingQt applications

2 - Execute the Main Loop (i.e. Eval + MainLoop in one function)

3 - Maximum nested events is 255 events

This function is used to write tests that contains events

Syntax:

ringvm_runcode(cCode)