BlitzMax/Modules/BASIC/BlitzMax runtime

The Blitz runtime module provides low level functionality required by BlitzMax applications when they are running. This includes things like memory management, exception handling and string and array operations.

Much of the functionality provided by this module is hidden from application programmers, but is instead used 'behind the scenes' by the compiler. However, there are some very useful commands for debugging, memory management and simple standard IO.

=Globals=

AppDir
Global AppDir$="bbAppDir"

Description: Application directory

Information: The AppDir global variable contains the fully qualified directory of the currently executing application. An application's initial current directory is also set to AppDir when an application starts.

Example: ' appdir.bmx ' requests the user to select a file from the application's directory

Print "Application Directory="+AppDir$

file$=RequestFile("Select File to Open","",False,AppDir$)

Print "file selected was :"+file

AppFile
Global AppFile$="bbAppFile"

Description: Application file name

Information: The AppFile global variable contains the fully qualified file name of the currently executing application.

Example: ' appfile.bmx

Print "This program's executable is located at "+AppFile$

AppTitle
Global AppTitle$="bbAppTitle"

Description: Application title

Information: The AppTitle global variable is used by various commands when a default application title is required - for example, when opening simple windows or requesters. Initially, AppTitle is set the value "BlitzMax Application". However, you may change AppTitle at any time with a simple assignment.

AppArgs
Global AppArgs$[]="bbAppArgs"

Description: Arguments passed to the application at startup

Information: The AppArgs global array contains the command line parameters sent to an application when it was started. The first element of AppArgs always contains the name of the application. However, the format of the name may change depending on how the application was launched. Use AppDir or AppFile for consistent information about the applications name or directory.

Example: ' appargs.bmx ' print the command line arguments passed to the program at runtime

Print "Number of arguments = "+AppArgs.length

For a$=EachIn AppArgs Print a$ Next

LaunchDir
Global LaunchDir$="bbLaunchDir"

Description: Directory from which application was launched

Information: The LaunchDir global variable contains the current directory at the time the application was launched. This is mostly of use to command line tools which may need to access the 'shell' current directory as opposed to the application directory.

Example: ' launchdir.bmx

Print "This program was launched from "+LaunchDir$

=Functions=

RuntimeError
Function RuntimeError( message$ )

Description: Generate a runtime error

Information: Throws a TRuntimeException.

Example: ' runtimeerror.bmx

If a=0 RuntimeError "This program has failed badly."

DebugStop
Function DebugStop

Description: Stop program execution and enter debugger

Information: If there is no debugger present, this command is ignored.

DebugLog
Function DebugLog( message$ )

Description: Write a string to debug log

Information: If there is no debugger present, this command is ignored.

Comment: note that, unlike Assert, DebugLog will get compiled regardless of the compilation mode - just that nothing is printed in Release mode.

OnEnd
Function OnEnd( fun )

Description: Add a function to be called when the program ends

Information: OnEnd allows you to specify a function to be called when the program ends. OnEnd functions are called in the reverse order to that in which they were added.

Example: ' onend.bmx

Function cleanup Print "cleaning up" End Function

OnEnd cleanup Print "program running" End	'the cleanup function will be called at this time

ReadStdin
Function ReadStdin$

Description: Read a string from stdin

Returns: A string read from stdin. The newline terminator, if any, is included in the returned string.

WriteStdout
Function WriteStdout( str$ )

Description: Write a string to stdout

Information: Writes str to stdout and flushes stdout.

WriteStderr
Function WriteStderr( str$ )

Description: Write a string to stderr

Information: Writes str to stderr and flushes stderr.

Delay
Function Delay( millis )

Description: Wait for a given number of milliseconds

Information: Delay suspends program execution for at least millis milliseconds. A millisecond is one thousandth of a second.

MilliSecs
Function MilliSecs)

Description: Get millisecond counter

Returns: Milliseconds since computer turned on.

Information: MilliSecs returns the number of milliseconds elapsed since the computer was turned on. A millisecond is one thousandth of a second.

MemAlloc
Function MemAlloc:Byte Ptr( size )

Description: Allocate memory

Returns: A new block of memory size bytes long

MemFree
Function MemFree( mem:Byte Ptr )

Description: Free allocated memory

Information: The memory specified by mem must have been previously allocated by MemAlloc or MemExtend.

MemExtend
Function MemExtend:Byte Ptr( mem:Byte Ptr,size,new_size )

Description: Extend a block of memory

Returns: A new block of memory new_size bytes long

Information: An existing block of memory specified by mem and size is copied into a new block of memory new_size bytes long. The existing block is released and the new block is returned.

MemClear
Function MemClear( mem:Byte Ptr,size )

Description: Clear a block of memory to 0

MemCopy
Function MemCopy( dst:Byte Ptr,src:Byte Ptr,size )

Description: Copy a non-overlapping block of memory

MemMove
Function MemMove( dst:Byte Ptr,src:Byte Ptr,size )

Description: Copy a potentially overlapping block of memory

GCSetMode
Function GCSetMode( mode )

Description: Set garbage collector mode

Information: mode can be one of the following: 1 : automatic GC - memory will be automatically garbage collected 2 : manual GC - no memory will be collected until a call to GCCollect is made The default GC mode is automatic GC.

GCSuspend
Function GCSuspend

Description: Suspend garbage collector

Information: GCSuspend temporarily suspends the garbage collector. No garbage collection will be performed following a call to GCSuspend. Use GCResume to resume the garbage collector. Note that GCSuspend and GCResume 'nest', meaning that each call to GCSuspend must be matched by a call to GCResume.

GCResume
Function GCResume

Description: Resume garbage collector

Information: GCResume resumes garbage collection following a call to GCSuspend. See GCSuspend for more details.

GCCollect
Function GCCollect

Description: Run garbage collector

Returns: The amount of memory, in bytes, collected.

Information: This function will have no effect if the garbage collector has been suspended due to GCSuspend.

GCMemAlloced
Function GCMemAlloced

Description: Memory allocated by application

Returns: The amount of memory, in bytes, currently allocated by the application

Information: This function only returns 'managed memory'. This includes all objects, strings and arrays in use by the application.

GCEnter
Function GCEnter

Description: Private: do not use

GCLeave
Function GCLeave

Description: Private: do not use

HandleFromObject
Function HandleFromObject( obj:Object )

Description: Convert object to integer handle

Returns: An integer object handle

Information: After converting an object to an integer handle, you must later release it using the Release command.

HandleToObject
Function HandleToObject:Object( handle )

Description: Convert integer handle to object

Returns: The object associated with the integer handle

Example: ' handlefromobject.bmx

Type MyType Field x:Int=100 End Type

Local obj:MyType=New MyType Local handle:Int=HandleFromObject(obj) Print "handle = "+handle

Local obj2:MyType=MyType(HandleToObject(handle)) If obj=obj2 Then Print "obj = obj2" Print "x = "+obj2.x

Release handle

=Keywords=

Strict
Description: Set strict mode

Information: See BASIC Compatibility for more information on Strict mode programming.

Comment: In Strict mode automatic data typing is permitted. The default data type is Int.

Example: Rem Strict advises the BlitzMax compiler to report as errors all auto defined variables. End Rem

Strict

local a=10

b=20	'compiler error, strict mode means variables must be declared b4 use

SuperStrict
Description: Set SuperStrict mode

Comment: In SuperStrict mode data types must always be specified.

End
Description: End program execution

Example: Rem The End command causes a program to exit immediately. End Rem

Print "Hello!" End Print "This line will never be printed as the program has already been ended."

Rem
Description: Begin a remark block

Example: Rem

My Rem Example First created 9th August, 2004

(C)2050 Blitz Intergalactic Software Corporation

End Rem

Print "This program has no useful function"

Rem

Remarks are useful for making your program easily readable. You can leave details explaining the function of your program in a remarks section so that you and any other programmers that work with your code can more easily understand the workings of your program

End Rem

Print "Sorry." End

EndRem
Description: End a remark block

Example: Rem All code between Rem and EndRem is ignored by the BlitzMax compiler. Print "hello" End Rem

Print "goodbye"

True
Description: Constant integer of value 1

Example: Rem True is a Constant Integer assigned the value 1. End Rem

Print "True="+True

If True Print "This line will always be executed" EndIf

If Not True Print "This line will never be executed" EndIf

False
Description: Constant integer of value 0

Example: Rem False is a Constant Integer assigned the value 0. End Rem

Print "False="+False

If False Print "This code will never be executed" Endif

Pi
Description: Constant Pi value: 3.1415926535897932384626433832795

Example: Rem Pi is a Constant Double assigned the value 3.1415926535897932384626433832795 End Rem

Print "Pi="+Pi

Null
Description: Get Default Null value

Example: Rem Null is a BlitzMax Constant representing an empty Object reference. End Rem

Type mytype Field	atypevariable End Type

Global a:mytype

if a=null Print "a is uninitialized" a=new mytype if a<>null Print "a is initialized"

Byte
Description: Unsigned 8 bit integer Type

Example: Rem Byte is an unsigned 8 bit integer BlitzMax primitive type. End Rem

Local a:Byte

a=512;Print "a="+a	'prints 0 a=-1;Print "a="+a	'prints 255

Short
Description: Unsigned 16 bit integer Type

Example: Rem Short is an unsigned 16 bit integer BlitzMax primitive type. End Rem

Local a:Short

a=65536;Print "a="+a	'prints 0 a=-1;Print "a="+a	'prints 65535

Int
Description: Signed 32 bit integer Type

Example: Rem Int is a signed 32 bit integer BlitzMax primitive type. End Rem

Local a:Int

' the following values all print 0 as BlitzMax "rounds to zero" ' when converting from floating point to integer

a=0.1;Print a a=0.9;Print a a=-0.1;Print a a=-0.9;Print a

Long
Description: Signed 64 bit integer Type

Example: Rem Long is a signed 64 bit integer BlitzMax primitive type. End Rem

Const MAXLONG:Long=$7fffffffffffffff:Long Const MINLONG:Long=$8000000000000000:Long

Print "A long can have the maximum value of:"+MAXLONG Print "A long can have the minimum value of:"+MINLONG

Float
Description: 32 bit Floating point Type

Example: Rem Float is a 32 bit floating point BlitzMax primitive type. End Rem

Local a:Float

a=1

For i=1 To 8 Print a	a=a*0.1 Next

For i=1 To 8 a=a*10 Print a Next

Double
Description: 64 bit floating point Type

Example: Rem Double is a 64 bit floating point BlitzMax primitive type. End Rem

Local speedoflight:Double Local distance:Double Local seconds:Double

speedoflight=299792458:Double	'meters per second distance=149597890000:Double	'average distance in meters from earth sun

seconds=distance/speedoflight

Print "Number of seconds for light to travel from earth to sun="+seconds

String
Description: String Type

Example: Rem String is a BlitzMax container type containing a sequence of unicode characters. End Rem

quote:String=Chr(34) Print quote+"Hello World!"+quote

Object
Description: Object Type

Example: Rem Object is the base class of all BlitzMax types.

The following function attempts to cast from any object to the custom type TImage and returns true if the given object is an instance of TImage or an instance of a &Type derived from TImage. End Rem

Function IsImage(obj:Object) If TImage(obj) return True Return False End Function

Var
Description: Composite Type specifier for 'by reference' types

Example: Rem Var is a composite type containing a reference to a variable of the specified Type. End Rem

' the following illustrates parsing function parameters by reference

Function ReturnMultiplevalues(a Var,b Var,c Var) a=10 b=20 c=30 Return End Function

Local x,y,z

ReturnMultipleValues(x,y,z)

Print "x="+x	'10 Print "y="+y	'20 Print "z="+z	'30

Ptr
Description: Composite Type specifier for pointer types

Example: Rem Ptr is a composite type containing a pointer to a variable of the specified Type. End Rem

' the following illustrates the use of traditional c style pointers

Local c[]=[1,2,3,4] Local p:Int Ptr

p=c Print "pointer 'p' points to:"+p[0]	'1

p:+1 Print "pointer 'p' points to:"+p[0]	'2

p:+1 Print "pointer 'p' points to:"+p[0]	'3

p:+1 Print "pointer 'p' points to:"+p[0]	'4

If
Description: Begin a conditional block.

Example: Rem If begins a conditional block. End Rem

If 3<5 Print "3<5"	'single line if

If 5<7			'if block Print "5<7" EndIf

Then
Description: Optional separator between the condition and associated code in an If statement.

Example: Rem Then is an optional separator between the condition and the block of code following an If statement. End Rem

If 3<5 Then Print "3<5"

Else
Description: Else provides the ability for an If Then construct to execute a second block of code when the If condition is False.

Example: Rem Else provides the ability for an If Then construct to execute a second block of code when the If condition is false. End Rem

i=3

If i<5 Print "i<5" Else Print "i>=5"	'single line If Else

If i<5					'block style If Else Print "i<5" Else Print "i>=5" EndIf

ElseIf
Description: ElseIf provides the ability to test and execute a section of code if the initial condition failed.

Example: Rem ElseIf provides the ability to test and execute a section of code if the initial condition failed. End Rem

age=Int( Input("How old Are You?") )

If age<13 Print "You are young" ElseIf age<20 Print "You are a teen!" Else Print "You are neither young nor a teen" EndIf

EndIf
Description: Marks the end of an If Then block.

Example: Rem EndIf marks the end of an If Then block. End Rem

i=5

If i<10 Print "i<10" EndIf

For
Description: Marks the start of a loop that uses an iterator to execute a section of code repeatedly.

Example: Rem For marks the start of a loop that uses an iterator to execute a section of code repeatedly. End Rem

' print 5 times table

For i=1 to 12 Print "5*"+i+"="+5*i Next

To
Description: Followed by a constant which is used to calculate when to exit a For..Next loop.

Example: Rem Followed by a constant which is used to calculate when to exit a For..Next loop. End Rem

For i=1 To 5 Print i Next

Step
Description: Specifies an optional constant that is used to increment the For iterator.

Example: Rem Specifies an optional constant that is used to increment the For iterator. End Rem

' count backwards from 10 to 0

For i=10 to 0 step -1 Print i Next

Next
Description: End a For block

Example: Rem Marks the end of a For section. End Rem

For i=1 To 5;Print i;Next

EachIn
Description: Iterate through an array or collection

Example: Rem Specifies a BlitzMax collection type whose values are assigned sequentially to the For iterator. End Rem

Local a[]=[0,5,12,13,20]

For b=EachIn a	Print b Next

While
Description: Execute a block of code while a condition is True

Example: Rem While executes the following section of code repeatedly while a given condition is true. End Rem

Graphics 640,480 While Not KeyHit(KEY_ESCAPE)	'loop until escape key is pressed Cls For i=1 to 200 DrawLine rnd(640),rnd(480),rnd(640),rnd(480) Next Flip Wend

Wend
Description: End a While block

Example: Rem Wend marks the end of a While section. End Rem

While i<5 Print i	i:+1 Wend

EndWhile
Description: End a While block

Repeat
Description: Execute a block of code until a termination condition is met, or forever

Example: Rem Repeat executes the following section of code until a terminating condition is true. End Rem

Repeat Print i	i:+1 Until i=5

Until
Description: Conditionally continue a Repeat block

Example: Rem Until marks the end of a Repeat block and is followed by a terminating condition. End Rem

i=2 Repeat Print i	i:*2 Until i>1000000

Forever
Description: Continue a Repeat block forever

Example: Rem Forever is an alternate ending to a Repeat block that will cause the loop to always repeat. End Rem

Repeat Print i+" Ctrl-C to End!" i:+1 Forever

Select
Description: Begin a Select block

Example: Rem Select begins a block featuring a sequence of multiple comparisons with a single value. End Rem

a=Int( Input("Enter Your Country Code ") )

Select a	Case 1 Print "You are from America" Case 44 Print "You are from the United Kingdom" Case 62 Print "You are from Australia" Case 64 Print "You are from New Zealand" Default Print "I cannot tell which country you are from" End Select

EndSelect
Description: End a Select block

Example: Rem EndSelect marks the end of a Select block. End Rem

SeedRnd MilliSecs

a=Rand(5)

Select a	Case 1 Print "one" Case 2 Print "two" Case 3 Print "three" Case 4 Print "four" Case 5 Print "five" Default Print "Program Error" End Select

Case
Description: Conditional code inside a Select block

Example: ' case.bmx

' Case performs a comparison with the preceeding value(s) and that ' listed in the enclosing Select statement:

a=Int( Input("Enter a number between 1 and 5 ") )

Select a	Case 1 Print "You think small" Case 2 Print "You are even tempered" Case 3,4 Print "You are middle of the road" Case 5 Print "You think big" Default Print "You are unable to follow instructions" End Select

Default
Description: Default code inside a Select block

Example: Rem Default is used in a Select block to mark a code section that is executed if all prior Case statements fail. End Rem

a$=Input("What is your favorite color?") a$=Lower(a$)	'make sure the answer is lower case

Select a$	Case "yellow" Print "You a bright and breezy" Case "blue" Print "You are a typical boy" Case "pink" Print "You are a typical girl" Default Print "You are quite unique!" End Select

Exit
Description: Exit enclosing loop

Example: Rem Exit causes program flow to exit the enclosing While, Repeat or For loop. End Rem

Repeat Print n	n:+1 If n=5 Exit Forever

Continue
Description: Continue execution of enclosing loop

Example: Rem Continue causes program flow to return to the start of the enclosing While, Repeat or For program loop End Rem

For i=1 To 20 If i Mod 2 Continue Print i Next

Const
Description: Declare a constant

Example: Rem Const defines the preceeding variable declaration as constant. End Rem

Const ON=True Const OFF=False

Const TWOPI#=2*Pi

Print TWOPI

Local
Description: Declare a Local variable

Example: Rem Local defines a variable as local to the Method or Function it is defined meaning it is automatically released when the function returns. End Rem

Function TestLocal Local	a a=20 Print "a="+a Return End Function

TestLocal Print "a="+a	'prints 0 or if in Strict mode is an error as a is only local to the TestLocal function

Global
Description: Declare a Global variable

Example: Rem Global defines a variable as Global allowing it be accessed from within Methods and Functions. End Rem

Global a=20

Function TestGlobal Print "a="+a End Function

TestGlobal Print "a="+a

Field
Description: Declare a Field variable

Example: Rem Field is used to declare the member variable(s) of a type. End Rem

Type TVector Field	x,y,z End Type

Local a:TVector=New TVector

a.x=10 a.y=20 a.z=30

Function
Description: Begin a Function declaration

Example: Rem Function marks the beginning of a BlitzMax function declaration.

When a function does not return a value the use of brackets when calling the function is optional. End Rem

Function NextArg(a$) Local	p p=Instr(a$,",") If p 		NextArg a$[p..] Print a$[..p-1] Else Print a$	EndIf End Function

NextArg("one,two,three,four")

NextArg "22,25,20"	'look ma, no brackets

EndFunction
Description: End a Function declaration

Example: Rem Function marks the end of a BlitzMax function declaration. End Rem

Function RandomName$ local a$[]=["Bob","Joe","Bill"] Return a[Rnd(Len a)] End Function

For i=1 To 5 Print RandomName$ Next

Return
Description: Return from a Function

Example: Rem Return exits a BlitzMax function or method with an optional value. The type of return value is dictated by the type of the function. End Rem

Function CrossProduct#(x0#,y0#,z0#,x1#,y1#,z1#) Return x0*x1+y0*y1+z0*z1 End Function

Print "(0,1,2)x(2,3,4)="+CrossProduct(0,1,2,2,3,4)

Function LongRand:Long Return (Rand($80000000,$7fffffff) Shl 32)|(Rand($80000000,$7fffffff)) End Function

Print "LongRand="+LongRand Print "LongRand="+LongRand

Type
Description: Begin a user defined Type declaration

Example: Rem Type marks the beginning of a BlitzMax custom type.

Standard BlitzMax types use a preceeding "T" naming convention to differentiate themselves from standard BlitzMax variable names. End Rem

Type TVector Field	x,y,z End Type

Local a:TVector=New TVector

a.x=10 a.y=20 a.z=30

EndType
Description: End a user defined Type declaration

Example: Rem EndType marks the end of a BlitzMax custom type. End Rem

Type TVector Field	x,y,z End Type

Local a:TVector=New TVector

a.x=10 a.y=20 a.z=30

Extends
Description: Specify user defined Type supertype

Comment: The Type inherits a given base Type.

Example: Rem Extends is used in a BlitzMax Type declaration to derive the Type from a specified base class. End Rem

Type TShape Field	xpos,ypos Method Draw Abstract End Type

Type TCircle Extends TShape Field	radius Function Create:TCircle(x,y,r) Local c:TCircle=New TCircle c.xpos=x;c.ypos=y;c.radius=r Return c	End Function Method Draw DrawOval xpos,ypos,radius,radius End Method End Type

Type TRect Extends TShape Field	width,height Function Create:TRect(x,y,w,h) Local r:TRect=New TRect r.xpos=x;r.ypos=y;r.width=w;r.height=h Return r	End Function Method Draw DrawRect xpos,ypos,width,height End Method End Type

Local 	shapelist:TShape[4] Local	shape:TShape

shapelist[0]=TCircle.Create(200,50,50) shapelist[1]=TRect.Create(300,50,40,40) shapelist[2]=TCircle.Create(400,50,50) shapelist[3]=TRect.Create(200,180,250,20)

Graphics 640,480 While Not KeyHit(KEY_ESCAPE) Cls For shape=EachIn shapelist shape.draw Next Flip Wend End

Method
Description: Begin a Method declaration

Comment: Methods are instance-specific functions.

Example: Rem Method marks the beginning of a BlitzMax custom type member function. End Rem

Type TPoint Field	x,y

Method ToString$ Return x+","+y End Method End Type

a:TPoint=New TPoint Print a.ToString

EndMethod
Description: End a Method declaration

Example: Rem EndMethod marks the end of a BlitzMax Method declaration. End Rem

Type TPoint Field	x,y

Method ToString$ Return x+","+y End Method End Type

a:TPoint=New TPoint Print a.ToString

Abstract
Description: Denote a Type or Method as Abstract

Comment: The Type or Method must be extended (compilation will fail if it was not extended).

Example: Rem A BlitzMax type that contains Abstract methods becomes abstract itself. Abstract types are used to define interfaces that extending types must implement before they can be used to create new instances.

In the following code TShape is an abstract type in that you can not create a TShape but anything extending a TShape must implement a Draw method. End Rem

Type TShape Field	xpos,ypos Method Draw Abstract End Type

Type TCircle Extends TShape Field	radius Function Create:TCircle(x,y,r) Local c:TCircle=New TCircle c.xpos=x;c.ypos=y;c.radius=r Return c	End Function Method Draw DrawOval xpos,ypos,radius,radius End Method End Type

Type TRect Extends TShape Field	width,height Function Create:TRect(x,y,w,h) Local r:TRect=New TRect r.xpos=x;r.ypos=y;r.width=w;r.height=h Return r	End Function Method Draw DrawRect xpos,ypos,width,height End Method End Type

Local 	shapelist:TShape[4] Local	shape:TShape

shapelist[0]=TCircle.Create(200,50,50) shapelist[1]=TRect.Create(300,50,40,40) shapelist[2]=TCircle.Create(400,50,50) shapelist[3]=TRect.Create(200,180,250,20)

Graphics 640,480 While Not KeyHit(KEY_ESCAPE) Cls For shape=EachIn shapelist shape.draw Next Flip Wend End

Final
Description: Denote a Type or Method as Final

Comment: The Type or Method is not extendable.

Example: Rem Final stops methods from being redefined in super classes. End Rem

Type T1	Method ToString$ Final Return "T1" End Method End Type

Type T2 Extends T1	Method ToString$	'compile time error "Final methods cannot be overridden" Return "T2" End Method End Type

New
Description: Create an instance of a user defined Type

Example: Rem New creates a BlitzMax variable of the Type specified. End Rem

Type MyType Field	a,b,c End Type

Local t:MyType t=New MyType t.a=20

Print t.a

' if a new method is defined for the type it will also be called

Type MyClass Field	a,b,c Method New Print "Constructor invoked!" a=10 End Method End Type

Local c:MyClass c=New MyClass Print c.a

Self
Description: Reference to this Method's Object instance

Comment: Allows an object access to its own instance (not needed in most cases).

Example: Rem Self is used in BlitzMax Methods to reference the invoking variable. End Rem

Type MyClass Global	count Field	id Method New id=count count:+1 ClassList.AddLast(Self)	'adds this new instance to a global list End Method End Type

Global ClassList:TList

classlist=New TList

Local c:MyClass

c=New MyClass c=New MyClass c=New MyClass

For c=EachIn ClassList Print c.id Next

Super
Description: Reference to the Super Type Object instance

Comment: Allows an object access to its parent type (the type that it extends).

Example: Rem Super evaluates to Self cast to the method's immediate base class. End Rem

Type TypeA Method Report Print "TypeA reporting" End Method End Type

Type TypeB Extends TypeA Method Report Print "TypeB Reporting" Super.Report End Method End Type

b:TypeB=New TypeB b.Report

Delete
Description: Reserved for future expansion

Example: Rem Reserved for future expansions. End Rem

Release
Description: Release an integer Object handle

Example: Rem Release removes the internal reference caused by creating an integer handle to a type. End Rem

Type MyType Field bigmap[1024*1024] End Type

GCCollect Print GCMemAlloced

a=New MyType GCCollect Print GCMemAlloced

Release a GCCollect Print GCMemAlloced

Public
Description: Public makes a Constant, Global variable or Function accessible from outside the current source file (Default)

Example: Rem Public makes a variable, function or method accessible from outside the current source file (default). End Rem

Public

Global	Score,Lives,Health

Private

Global	posx,posy,posz

Private
Description: Private makes a Constant, Global variable or Function only accessible from within the current source file

Example: Rem Private makes a variable, function or method only accessible from within the current source file. End Rem

Public

Global	Score,Lives,Health

Private

Global	posx,posy,posz

Extern
Description: Extern marks the beginning of an external list of Function declarations

Example: Rem Extern marks the beginning of an external list of function declarations. End Rem

Extern Function puts( str$z ) Function my_puts( str$z )="puts" End Extern

puts "Using clib's put string!" my_puts "Also using clib's put string!"

EndExtern
Description: EndExtern marks the End of an Extern section

Example: Rem EndExtern marks the end of an Extern section. End Rem

Extern Function puts( str$z ) End Extern

puts "Using clib's put string!"

Module
Description: Declare Module scope and identifier

Information: See Modules for more information.

Example: Rem The Module keyword advises the BlitzMax program maker BMK to create a code module from the source file. End Rem

Module PUB.Sequencer

ModuleInfo "Framework: Audio Sequencer for use with FreeAudio" ModuleInfo "Copyright: Blitz Research Ltd" ModuleInfo "Author: Simon Armstrong" ModuleInfo "Version: 1.00"

ModuleInfo
Description: Define Module properties

Example: Rem ModuleInfo allows properties such as Author and Copyright to be included in a module file. End Rem

Module PUB.Sequencer

ModuleInfo "Framework: Audio Sequencer for use with FreeAudio" ModuleInfo "Copyright: Blitz Research Ltd" ModuleInfo "Author: Simon Armstrong" ModuleInfo "Version: 1.00"

Incbin
Description: Embed a data file

Example: Rem IncBin embeds an external data file in a BlitzMax program that can then be read using the "incbin::" device name. End Rem

' code snippet from demos/firepaint/firepaint.bmx

Incbin "stars.png"

Local stars=LoadImage( "incbin::stars.png" )

IncbinPtr
Description: Get start address of embedded data file

Example: Rem IncBinPtr returns a byte pointer to the specified embedded binary file. End Rem

Incbin "incbinptr.bmx"

Local p:Byte Ptr=IncbinPtr("incbinptr.bmx") Local bytes=IncbinLen("incbinptr.bmx")

Local s$=String.FromBytes(p,bytes)

Print "StringFromBytes(p,bytes)="+s$

IncbinLen
Description: Get length of embedded data file

Example: Rem IncBinLen returns the size in bytes of the specified embedded binary file. End Rem

Incbin "incbinlen.bmx"

Local p:Byte Ptr=IncbinPtr("incbinlen.bmx") Local bytes=IncbinLen("incbinlen.bmx")

Local s$=StringFromBytes(p,bytes)

Print "StringFromBytes(p,bytes)="+s$

Include
Description: Include effectively 'inserts' the specified file into the file being compiled.

Framework
Description: Framework builds the BlitzMax application with only the Module specified rather than all modules installed.

Comment: If you specify some module with Framework, only that module and ones it imports are compiled with your code. You can then import additional modules using Import. Common framework modules are Brl.Basic and Brl.Max2D, for console and 2d applications respectively.

Import
Description: Import declarations from a Module or source file

Example: Rem
 * Import specifies the external BlitzMax modules and source files used by the program.

End Rem

Framework BRL.GlMax2D

Import BRL.System

Graphics 640,480,32

While Not KeyHit(KEY_ESCAPE) Cls DrawText "Minimal 2D App!",0,0 Flip Wend

Assert
Description: Throw a RuntimeError if a condition is False

Comment: Assert throws a runtime error in Debug mode.

Example: Rem Assert generates a BlitzMax runtime error if the specified condition is false. End Rem

a=LoadImage("nonexistant image file") Assert a,"Image Failed to Load"

Goto
Description: Transfer program flow to specified label

Comment: Goto does not work in SuperStrict or Strict mode. Also, labels are limited to DefData.

Example: Rem Causes program execution to jump to the #label specified. End Rem

Print "one" Goto here Print "two" Print "three"
 * 1) here

Try
Description: Begin declaration of a Try block

Comment: A Try block attempts to catch an exception that might have been thrown between Try and Catch and attempts to handle the exception (instead of ending the program).

Example: Rem Begin declaration of a Try block. End Rem

Try Repeat a:+1 Print a		If a>20 Throw "chunks" Forever Catch a$	Print "caught exception "+a$ EndTry

EndTry
Description: End declaration of a Try block

Example: Rem EndTry EndTry marks the end of a Try block. End Rem

Catch
Description: Catch an exception Object in a Try block

Example: Rem Catch defines an exception handler following a Try..EndTry Block. End Rem

Try Repeat a:+1 Print a		If a>20 Throw "chunks" Forever Catch a$	Print "caught exception "+a$ EndTry

Throw
Description: Throw an exception Object to the enclosing Try block

Example: Rem Throw generates a BlitzMax exception. End Rem

Try Repeat a:+1 Print a		If a>20 Throw "chunks" Forever Catch a$	Print "caught exception "+a$ EndTry

DefData
Description: Define class BASIC style data

Example: ' defdata.bmx

ReadData name$ ReadData age,skill

Print "name="+name+" age="+age+" skill="+skill

DefData "Simon",37,5000

ReadData
Description: Read classic BASIC style data

RestoreData
Description: Restore classic BASIC style data

Example: ' restoredata.bmx

For i=1 To 5 RestoreData mydata	'reset the data pointer everly loop so we don't read past the end ReadData name$,age,skill Print "name="+name+" age="+age+" skill="+skill Next


 * 1) mydata	'program label that can be used with the RestoreData command

DefData "Simon",37,5000

And
Description: Conditional 'And' binary operator

Example: Rem And is a boolean operator that performs the AND function. End Rem

For i=1 To 10 If i>3 And i<6 Print "!" Else Print i Next

Or
Description: Conditional 'Or' binary operator

Example: Rem Or is a boolean operator that performs the OR function. End Rem

For i=1 To 5 If i=2 Or i=4 Print "!" Else Print i Next

Not
Description: Conditional 'Not' binary operator

Example: Rem Not is a boolean unary operator that performs the NOT function. End Rem

Print Not 0		'prints 1 (TRUE) Print Not 20		'prints 0 (FALSE)

Shl
Description: Bitwise 'Shift left' binary operator

Example: Rem Shl is a binary operator that performs the shift to left function. End Rem

b=1 For i=1 To 32 Print Bin(b) b=b Shl 1 Next

Shr
Description: Bitwise 'Shift right' binary operator

Example: Rem Shr is a binary operator that performs the shift to right function. End Rem

b=-1 For i=1 To 32 Print Bin(b) b=b Shr 1 Next

Sar
Description: Bitwise 'Shift arithmetic right' binary operator

Example: Rem Sar is a binary operator that performs the arithmetic shift to right function. End Rem

b=$f0f0f0f0 For i=1 To 32 Print Bin(b) b=b Sar 1 Next

Len
Description: Number of characters in a string or elements in an array

Comment: You can also use the length field of an array or string as they are objects.

Example: Rem Len is a BlitzMax operator that returns the number of elements in a container Type. End Rem

a$="BlitzMax Rocks" Print Len a$	'prints 14

Local b[] Print Len b		'prints 0

b=New Int[20] Print Len b		'prints 20

Abs
Description: Numeric 'absolute value' unary operator

Example: Rem Abs is a mathematical operator that performs the Absolute function. End Rem

For f#=-1 To 1 Step 0.125 Print "Abs "+f+"="+Abs f Next

Mod
Description: Numeric 'modulus' or 'remainder' binary operator

Example: Rem Mod is a mathematical operator that performs the Modulo function. End Rem

For i=6 to -6 Step -1 Print i+" Mod 3="+(i Mod 3) Next

Sgn
Description: Numeric 'sign' unary operator

Example: Rem Sgn is a mathematical operator that returns the sign of a value. End Rem

Print Sgn 50	'1 Print Sgn 0	'0 Print Sgn -50	'-1

Min
Description: Numeric 'minimum' builtin function

Returns: The lesser of the two numeric arguments

Max
Description: Numeric 'maximum' builtin function

Returns: The larger of the two numeric arguments

Varptr
Description: Find the address of a variable

Example: Rem Varptr returns the address of a variable in system memory. End Rem

Local a:Int Local p:Int Ptr

a=20 p=Varptr a Print p[0]

SizeOf
Description: Size, in bytes, occupied by a variable, string, array or object

Example: Rem SizeOf returns the number of bytes of system memory used to store the variable. End Rem

Type MyType Field a,b,c End Type

Local t:MyType Print SizeOf t	'prints 12

Local f! Print SizeOf f	'prints 8

Local i Print SizeOf i	'prints 4

Local b:Byte Print SizeOf b	'prints 1

a$="Hello World" Print SizeOf a	'prints 22 (unicode characters take 2 bytes each)

Asc
Description: Get character value of the first character of a string

Example: Rem Asc returns the unicode value of the first character of a string. End Rem

Print Asc("A")	'65 Print "A"[0]	'65 - equivalent index style implementation

Chr
Description: Create a string of length 1 with a character code

Example: Rem Chr returns a String of length 1 containing the unicode character of the value. End Rem

Print Chr(65)	'A