TweetFollow Us on Twitter

MacForth Calc
Volume Number:9
Issue Number:4
Column Tag:Jörg's Folder

Object Programming in MacForth

Porting the simple calculator to MacForth

By Jörg Langowski, MacTech Magazine Regular Contributing Author

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Those of you who have been with us from the very beginning, V1#1, will remember that this column started out as a Forth column, and that my first programming examples were in MacForth. At the time when the Macintosh was introduced, this was one of the few development systems for the rest of us, and you see, it has stayed around all the time.

In fact, MacForth is the only Forth system for the Macintosh that is still commercially supported; you have read about others here, but they are in the public domain (like Mops and Yerk) or ‘almost’ public domain (like Mach2). Since numerous calls to the readership for MacForth article submissions were of no avail, I’ve finally decided to write an example program myself to bring MacForth back into the memory of the MacTech readers and show how nicely you can write object-oriented code in MacForth.

So here we’re back to our roots: MacTutor is back to MacTech, and J.L. is back to MacForth.

Why bother?

Those of you who would never touch Forth with a ten-foot reverse Pole (although I’m only 5’11”), please don’t turn to the next article immediately. I’ll give you some basic notions that may help you to understand the example.

A Forth program consists of a sequence of words. Each word is a routine that works by taking parameters off a stack and eventually leaving results there. Any number can be considered as just a word that leaves its value on the stack. Forth development systems normally accept words interactively or from a file and execute them immediately. All words are separated by blanks. If you type

 3

there will be a 3 on top of the stack. The sequence

 3 4 +

will put the numbers 3 and 4 on the stack, and then compute their sum, which is left on the stack. All in all, Forth works like an HP calculator, using reverse Polish notation.

How about writing programs? There are two “words”, : (colon) and ; (semicolon), which start and end ‘definitions’. A definition looks like this:

: test 3 4 + ;

This defines the new word test which simply executes the summation of 3 and 4 and leaves the result on the stack. Thus, the first word after the colon is the name of the newly defined word, and the remaining sequence of words is not executed, but compiled into a dictionary and by some means or other linked to the name which is kept in a vocabulary. When the newly defined word is then executed, it will behave as if one had entered the initial sequence of words in the definition.

Forth programs are typically written by splitting up the program task into very small units and coding each of them into a word definition, just if one was to write a C program by coding lots of small routines and assemble them into larger ones. A very structured approach, which is easy to do with Forth because the low-level definitions are compiled immediately (by typing them in or loading them from a file), and they can be tested interactively before using them in the higher-level routines. This interactive, incremental compiling is one of the great strengths of Forth.

This concludes my short sales pitch for Forth. Before we jump right into the middle of things with our example, some small Forth words that you’ll come across in the listing:

! (exclamation mark) takes two values from the stack, an address (top) and a number (underneath). It stores the number into the 32-bit long word at address. c! stores the value into the byte at address.

@ (at sign) takes the address from top of stack and gets the 32-bit longword stored there. c@ gets the 8-bit value at address.

dup duplicates the value on top of the stack, drops it, and exchanges the two top values.

+, -, *, / are operators that do exactly what you would expect to the two top values on the stack.

if then brackets code that is conditionally executed if the top of the stack is non-zero.

Other control structures: do loop, case endcase, begin until, begin again. Details about their functioning can be found in any good book on Forth. I recommend “Starting Forth” by Leo Brodie, published by Forth, Inc. But now to the example.

An arithmetic expression parser in Forth

For the example, I decided to convert the calculator program that I presented in V9#1 from C++ to Forth (I know there are some people who’ll try to kill me for this). It is not as ridiculous as it seems: The original program was written as an example for object programming, and you’ll see that the object oriented extensions contained in MacForth make it relatively easy to port the code. In fact, the only places where I really had to pay attention to bugs were the routines which input and parsed a string from the keyboard, and entering and retrieving names from the symbol table. The whole object-oriented structure of the program worked almost immediately the way I typed it in.

The calculator works just like the C++ example: it reads in a line with an arithmetic expression, analyzes it and constructs a ‘syntax tree’ representation from it, and finally evaluates that syntax tree and prints the result (in order to understand this month’s example it helps to get out your old V9#1 copy and compare to the C++ code). In the C++ example, we defined classes for the different objects that make up the syntax tree and constructed an instance of one of those classes for each node of the tree. Those nodes could be: the operators +,-,*,/ and =, which each connect two other nodes, the unary minus, and the end nodes, numbers and variables.

To reconstruct the C++ example, let’s first see how object-oriented programming is achieved in MacForth. MacForth provides so-called acting elements or actels, which contain their own private data structure and to which messages can be sent; so these are objects. An actel is defined first through its data structure; MacForth provides possibilities for structure definitions. You can see this at the beginning of the listing. As an example, the structure corresponding to a dyadic operator is defined by

structure dyadheader
 minElemHeaderSize +
 handle:+left
 handle:  +right
structure.end

This definition does not create the object; it only defines a word dyadheader which will leave the total size of the structure on the stack when executed, and other words (+left, +right) that will add a number to the top of stack equal to the offset for the corresponding element in the structure. So you may define

create my.dyad dyadheader allot

which will allocate space in the dictionary for one copy of this structure, my.dyad, and then access the two fields of the structure by writing

my.dyad +left

which leaves the address of the ‘left’ field of the structure on the stack. Remark on the side: the field name in MacForth structure definitions is not local to the structure, but visible globally. Thus, you cannot define two different structures which have a field with the same name at different offsets. This is one limitation that one has to live with.

You see that there is some space created at the beginning of the structure (of length minElemHeaderSize) which contains fields ‘for internal use’. In the current implementation, this size is 16 bytes. The first longword of these reserved bytes containes a machine instruction that jumps to the method selector of the class, and the last longword contains the total size of the header.

The messages that one sends to MacForth actels are again Forth words, which by convention start with ‘>>’. There are a couple of predefined messages, the ones interesting to us are >>New (make a new object on the heap), >>Discard (remove the object from the heap), >>Empty (fill the object’s data space with zeros) and >>Room (resize the object). New messages are created by writing e.g.

1000  message  >>eval
1001  message  >>set

as in the example. This assigns the message numbers 1000 and 1001 to the messages >>eval and >>set. Every message must have a unique number, that’s how they are distinguished. When a message is sent to an Actel, actually the message number is passed to a selector, which then calls the appropriate method. The selector, e.g. for the plus operator, is defined as follows:

1 selector: dyad.msgs
 ElemPanic
 dyad::New
 dyad::Discard
 drop
 inherited
;selector

1000 selector: plus.msgs
 dyad.msgs
 plus::Eval
;selector

First, a selector defines the basic methods used in dyadic operators. They are assigned increasing message numbers, starting with 1. The first word ElemPanic after the selector name dyad.msgs is the routine which is called if the message number is outside the range of the selector. Since this is the lowest level of methods, the routine called here will complain that the message number was not implemented. The next words correspond to message numbers 1 to 4, or >>New, >>Discard, >>Empty and >>Room. >>New will call the method dyad::New (the two colons are simpky my convention from C++; you may give the method any name you like), >>Discard calls dyad::Discard, >>Empty simply drops the top stack item (which is the handle of the object to which the message was sent), this means it does nothing; and >>Room is not handled by this class.

The selector plus.msgs assigns the method specific to the plus operator, its evaluation plus::eval, to the message number 1000, >>eval. This will be the highest level selector that is stored in the header of the plus operator objects and which is first executed when a plus object receives a message. If it is =1000, plus::Eval is called. If not, the next lower level selector, dyad.msgs, is invoked.

How are methods written? The calling sequence for a method is <parameters> <object> <message>. The message word calls the selector corresponding to the class of the object, which then calls the appropriate method. At that moment, the object’s handle is on the top of the stack, and any parameters underneath. The method must dereference the object handle, access its fields if necessary and do its things using the parameters and the object fields. As an example, look at the plus::Eval method again:

: plus::Eval ( handle -- value )
 h@ dup +left @ >>eval swap +right @ >>eval +

This method will get the handle to the left side of the plus operator (stored in the left field), which is an object, send it the message >>eval, then do the same thing to the right hand side, and finally add the results and leave the sum on the stack.

This column has not enough space for explaining all the methods in detail; with some intuition and ‘Forth thinking’, or better a MacForth manual, you will easily see the parallels between the code here and the C++ example. What is important to mention here is that for each class you need to define one instance of an object ‘by hand’, that is create its data structure on the heap. This is the ‘parent instance’; further instances of the same class are then made simply by copying the parent object. The parent objects of all the classes are made in the middle of the example code, where the selectors are also defined; look at the words make.dyad etc. The jump to the highest-level method selector is also stored in the parent object by ElemAction!.

In the next part of the code, the token scanning routine from the C++ example is recreated. Non-Forthers who are still reading, you may skip this; suffice it to say that each invocation of the word scan leaves the next token from the input stream on the stack, which can then be stored in the global variable token. For the Forthers, it should be easy to verify that this code is a typical example of the mess you have to deal with when you are doing input/output in Forth

After all these preliminaries, the port of the main parser code from C++ to Forth is quite easy. We have to rewrite the three routines that parse an expression, a term and a factor. All these routines can call each other recursively, so we have to use ‘deferred words’ to implement them. First, we define the routine names:

defer factor
defer term
defer expr

then we code the routines do.factor, do.term and do.expr, and finally we assign these routines to the deferred words:

token.for do.factor IS factor
token.for do.term IS term
token.for do.expr IS expr

The routines itself are a straight translation from C++; you may verify this from the example in V9#1. So you see, other than the strange message passing mechanism and the reverse Polish notation, Forth is just like C++! :-)

Of course, I could have written this example in Mops or Yerk as well; you may do that as an exercise for yourself. The code will be probably shorter in Mops, since many of the things that we did here explicitly (such as creating the initial parent objects) are done more or less implicitly in other object-oriented systems. But then, MacForth doesn’t claim to be a full object-oriented language, only a Forth with object-oriented extensions. You can see that these ’extensions’ go actually quite far, and provide a very good means to understand what is actually going on when a routine is selected through a method table.

At the end, let me say that I would have taken much more time doing this example if it weren’t for the incremental compiling of Forth in general and the excellent debugging facilities of MacForth. If one couldn’t analyze exactly what each little routine is doing to the stack at each point (which is possible with MacForth), one would get lost immediately even in a small piece of code like this.

Next time (two months from now) back to C++.

Listing: Calculator example in MacForth

 anew --calc--

structure dyadheader
 minElemHeaderSize +
 handle:+left
 handle:  +right
structure.end

structure unaryheader
 minElemHeaderSize +
 handle:+operand
structure.end

structure numheader
 minElemHeaderSize +
 long:  +value
structure.end

structure IDheader
 minElemHeaderSize +
 31 string: +name
structure.end

\
\ the symbol table is implemented as a vocabulary
\ use CONTEXT as template for symtab (see below)
\
global symtab

\
\ messages
\

1000  message  >>eval
1001  message  >>set

\ 
\ methods
\

: dyad::New  ( left\right\handle -- handle )
 dyadheader swap ElemNew 
 \ create space for new dyad, handle on stack
 dup h@ locals| selfaddr self |
 ( stack now: left\right )
 selfaddr +right ! selfaddr +left !
 self
;

: dyad::Discard ( handle -- )
 dup h@ +left @ >>Discard 
 dup h@ +right @ >>Discard
 to.heap
;

: plus::Eval ( handle -- value )
 h@ dup +left @ >>eval swap +right @ >>eval +
;

: minus::Eval ( handle -- value )
 h@ dup +left @ >>eval swap +right @ >>eval -
;

: times::Eval ( handle -- value )
 h@ dup +left @ >>eval swap +right @ >>eval *
;

: divide::Eval ( handle -- value )
 h@ dup +left @ >>eval swap +right @ >>eval /
;

: equals::Eval ( handle -- value )
 h@ dup +right @ >>eval swap +left @ >>set
;

: unary::New ( operand\handle -- handle)
 unaryheader swap ElemNew
 dup h@ locals| selfaddr self |
 selfaddr +operand !
 self 
;

: unary::Discard ( handle -- )
 dup h@ +operand @ >>Discard 
 to.heap
;

: uminus::Eval ( handle -- value )
 h@ +operand @ >>eval negate
;

: num::New ( value\handle -- handle )
 numheader swap ElemNew
 dup h@ locals| selfaddr self |
 selfaddr +value !
 self 
;

: num::Discard ( handle -- )
 to.heap
;

: inumber::Eval ( handle -- value )
 h@ +value @
;

: ID::New ( name\count\handle -- handle )
 IDheader swap ElemNew
 dup h@ locals| selfaddr self count |
 count selfaddr +name c! \ store count byte
 ( name ) selfaddr +name 1+ count cmove 
 \ store string data
 selfaddr +name symtab >>findname
 0= if
 0 selfaddr +name symtab >>AddEntry
 0= abort" Symbol table full"
 then
 self
;

: ID::Discard ( handle -- )
 to.heap
;

\ unfortunately, a MacForth vocabulary structure 
\ takes only 16-bit entries...
\ so we're limited to 16 bit integers
: ID::Eval ( handle -- value )
 h@ +name symtab >>findname 
 dup if symtab >>GetValue then
;

: ID::Set ( value\handle -- value )
 h@ locals| selfaddr value |
 selfaddr +name symtab >>findname 
 \ this is the only way to modify the value
 ?dup 0= abort" Tried to set a non-existing variable"
 symtab >>RemoveEntry drop
 value selfaddr +name symtab >>AddEntry
 0= abort" Symbol table full"
 value
;

\
\ variables for parent instances of classes
\
global PLUS
global MINUS
global TIMES
global DIVIDE
global EQUALS
global UMINUS
global INUMBER
global ID

\
\ make parent instances, define message selectors
\
: make.dyad ( -- dyadhandle )
 dyadheader makehandle locals| handle |
 dyadheader handle h@ 12 + !
 handle
;

1 selector: dyad.msgs
 ElemPanic
 dyad::New
 dyad::Discard
 drop
 inherited
;selector

1000 selector: plus.msgs
 dyad.msgs
 plus::Eval
;selector

make.dyad -> PLUS
token.for plus.msgs PLUS elemaction!

1000 selector: minus.msgs
 dyad.msgs
 minus::Eval
;selector

make.dyad -> MINUS
token.for minus.msgs MINUS elemaction!

1000 selector: times.msgs
 dyad.msgs
 times::Eval
;selector

make.dyad -> TIMES
token.for times.msgs TIMES elemaction!

1000 selector: divide.msgs
 dyad.msgs
 divide::Eval
;selector
 
make.dyad -> DIVIDE
token.for divide.msgs DIVIDE elemaction!

1000 selector: equals.msgs
 dyad.msgs
 equals::Eval
;selector
 
make.dyad -> EQUALS
token.for equals.msgs EQUALS elemaction!

: make.unary ( -- unaryhandle )
 unaryheader makehandle locals| handle |
 unaryheader handle h@ 12 + !
 handle
;

1 selector: unary.msgs
 ElemPanic
 unary::New
 unary::Discard
 drop
 inherited
;selector

1000 selector: uminus.msgs
 unary.msgs
 uminus::Eval
;selector
 
make.unary -> UMINUS
token.for uminus.msgs UMINUS elemaction!

: make.num ( -- numhandle )
 numheader makehandle locals| handle |
 numheader handle h@ 12 + !
 handle
;

1 selector: num.msgs
 ElemPanic
 num::New
 num::Discard
 drop
 inherited
;selector

1000 selector: inumber.msgs
 num.msgs
 inumber::Eval
;selector
 
make.num -> INUMBER
token.for inumber.msgs INUMBER elemaction!

1 selector: ID.low.msgs
 ElemPanic
 ID::New
 ID::Discard
 drop
 inherited
;selector

1000 selector: ID.msgs
 ID.low.msgs
 ID::Eval
 ID::Set
;selector
 
: make.ID ( -- IDhandle )
 IDheader makehandle locals| handle |
 IDheader handle h@ 12 + !
 handle
;

make.ID -> ID
token.for ID.msgs ID elemaction!

\ root token of the syntax tree
global root

\ token being scanned
global token

\ temp string storage
create tstring 80 allot
variable tlength

\ input scanned will go to PAD
\ restriction: one line per expression
\ extending this is left as an exercise to the reader
\ we don't use WORD because we don't want to have to use
\ blanks as delimiters everywhere
\
255 constant maxpad
variable chars.input

: fillpad 
 pad 1+ maxpad expect
 span @ chars.input !
 1 pad c!
;

\ gets a new character from standard input into PAD
\ reads new line if end of line encountered
: cget ( -- char )
 pad c@ chars.input @ >
 if fillpad then
 pad c@ pad + c@
 pad c@ 1+ pad c!
;

\ backspaces pointer to PAD
\ no action if already at beginning
: cputback ( char -- )
 pad c@ dup 1 > if 1- pad c! else drop then
 drop
; 

: ?digit ( char -- true or false)
 dup ascii 0 < not swap ascii 9 > not and 
;

: ?alfa ( char -- true or false)
 locals| ch |
 ch ascii a < not ch ascii z > not and
 ch ascii A < not ch ascii Z > not and or
;

: ?anum ( char -- true or false)
 dup ?digit swap ?alfa or
;

: syntax.error -1 abort" Syntax Error" ;

\ scan the remaining digits of a number
: scan.number ( ch -- ) 
 tstring c!
 1 tlength !
 80 1 do \ we don't expect more than 80 digits
 cget dup ?digit not if cputback leave then
  tstring i+ c!
 i 1+ tlength !
 loop
;

\ scan the remaining chars of an identifier
: scan.anum ( ch -- ) 
 tstring c!
 1 tlength !
 80 1 do \ we don't expect more than 80 chars
 cget dup ?anum not if cputback leave then
  tstring i+ c!
 i 1+ tlength !
 loop
;

\
\ constants
\
128 dup constant IDT
 1+dup constant INT
 1+dup constant EOLN
 1+constant BAD

: scan ( -- token )
 0 locals| c |
 begin
 cget -> c
 c case
 ascii ( ascii + range.of c endof
 ascii / of c endof
 ascii - of c endof
 ascii = of c endof
 13 of EOLN endof
 bl of 0 endof  \ just continue scan

 dup ?anum if
 dup ?digit if
 c scan.number INT swap 
 else
 c scan.anum IDT swap 
 then
 else
 BAD swap
 then
 endcase
 ?dup until
;

\
\ parser routines for expression, term, factor
\

: get.token.name ( -- name\count )
 tstring tlength @
;

: get.token.value ( -- value )
 bl tstring tlength @ + c!
 tstring 1- number
;

defer factor
defer term
defer expr

: do.factor ( -- factor-handle )
 0 locals| root |
 token
 case
 IDT of
 get.token.name ID >>New -> root
 scan dup -> token
 ascii = = IF
 scan -> token
 root expr EQUALS >>New -> root
 THEN
 endof
 INT of
 get.token.value INUMBER >>New -> root
 scan -> token
 endof
 ascii ( of
 scan -> token
 expr -> root
 token ascii ) = not IF syntax.error THEN                
 scan -> token
 endof
 ascii - of
 scan -> token
 factor UMINUS >>New -> root
 endof
 syntax.error
 endcase
 root
;

token.for do.factor IS factor

: do.term ( -- term-handle )
 factor locals| root |
 begin
 token
 case
 ascii * of
 scan -> token
 root term TIMES >>New -> root
 0 \ go on
 endof
 ascii / of
 scan -> token
 root term DIVIDE >>New -> root
 0 \ go on
 endof
 1 swap \ terminate
 endcase
 until
 root
;

token.for do.term IS term

: do.expr ( -- expr-handle )
 term locals| root |
 begin
 token
 case
 ascii + of
 scan -> token
 root term PLUS >>New -> root
 0 \ go on
 endof
 ascii - of
 scan -> token
 root term MINUS >>New -> root
 0 \ go on
 endof
 1 swap \ terminate
 endcase
 until
 root
;

token.for do.expr IS expr

: calc
 0 locals| root |
 begin
 cr ." Enter expression:" cr
 fillpad
 scan -> token
 expr -> root
 token BAD = if syntax.error then
 root 0= not if
 cr cr ." Result = " root >>Eval . cr
 root >>Discard
 then
 again
;

: setup.everything
 1000 context @ >>New -> symtab 
 make.dyad -> PLUS
 token.for plus.msgs PLUS elemaction!
 make.dyad -> MINUS
 token.for minus.msgs MINUS elemaction!
 make.dyad -> TIMES
 token.for times.msgs TIMES elemaction!
 make.dyad -> DIVIDE
 token.for divide.msgs DIVIDE elemaction!
 make.dyad -> EQUALS
 token.for equals.msgs EQUALS elemaction!
 make.unary -> UMINUS
 token.for uminus.msgs UMINUS elemaction!
 make.num -> INUMBER
 token.for inumber.msgs INUMBER elemaction!
 make.ID -> ID
 token.for ID.msgs ID elemaction!
;

: go
 setup.everything
 calc
;

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Stacks 3.5.5 - New way to create pages i...
Stacks is a new way to create pages in RapidWeaver. It's a plugin designed to combine drag-and-drop simplicity with the power of fluid layout. Features Fluid Layout: Stacks lets you build pages... Read more
Yasu 4.0.5 - System maintenance app.
Yasu was created with system administrators who service large groups of workstations in mind, Yasu (Yet Another System Utility) was made to do a specific group of maintenance tasks quickly within a... Read more
Things 3.2 - Elegant personal task manag...
Things is a task management solution that helps to organize your tasks in an elegant and intuitive way. Things combines powerful features with simplicity through the use of tags and its intelligent... Read more
iMazing 2.4.2 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
Google Chrome 61.0.3163.100 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
Quicken 4.6.4 - Complete personal financ...
Quicken makes managing your money easier than ever. Whether paying bills, upgrading from Windows, enjoying more reliable downloads, or getting expert product help, Quicken's new and improved features... Read more
Google Chrome 61.0.3163.100 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
iMazing 2.4.2 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
Quicken 4.6.4 - Complete personal financ...
Quicken makes managing your money easier than ever. Whether paying bills, upgrading from Windows, enjoying more reliable downloads, or getting expert product help, Quicken's new and improved features... Read more
Yasu 4.0.5 - System maintenance app.
Yasu was created with system administrators who service large groups of workstations in mind, Yasu (Yet Another System Utility) was made to do a specific group of maintenance tasks quickly within a... Read more

The best visual novels on mobile
Narrative games have been around for ages, but only now have they been creeping into the mainstream spotlight. These games tell some of the industry's finest stories, and they break new ground in terms of gameplay and mechanics regularly. Here are... | Read more »
The best new games we played this week -...
It's pretty much been one big release after another. We were privy to a bunch of surprises this week, with a lot of games we'd been waiting for quite some time dropping unexpectedly. We hope you're free this weekend, because there is a lot for... | Read more »
Stormbound: Kingdom Wars guide - how to...
Stormbound: Kingdom Wars is an excellent new RTS turned card battler out now on iOS and Android. Lovers of strategy will get a lot of enjoyment out of Stormbound's chess-like mechanics, and it's cardbased units are perfect for anyone who loves the... | Read more »
The best AR apps and games on iOS right...
iOS 11 has officially launched, and with it comes Apple's ARKit, a helpful framework that makes it easier than ever for developers to create mobile AR experiences. To celebrate the occassion, we're featuring some of the best AR apps and games on... | Read more »
Phoenix Wright: Ace Attorney - Spirit of...
Phoenix Wright: Ace Attorney - Spirit of Justice 1.00.00 Device: iOS Universal Category: Games Price: $.99, Version: 1.00.00 (iTunes) Description: ************************************************※IMPORTANT※・Please read the “When... | Read more »
Kpressor (Utilities)
Kpressor 1.0.0 Device: iOS Universal Category: Utilities Price: $4.99, Version: 1.0.0 (iTunes) Description: The ultimate ZIP compression application for iPhone and iPad. - Full integration of iOS 11 with support for multitasking.-... | Read more »
Find out how you can save £35 and win a...
Nothing raises excitement like a good competition, and we’re thrilled to announce our latest contest. We’ll be sending one lucky reader and a friend to the Summoners War World Arena Championship at Le Comedia in Paris on October 7th. It’s the... | Read more »
Another Lost Phone: Laura's Story...
Another Lost Phone: Laura's Story 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Another Lost Phone is a game about exploring the social life of a young woman whose phone you have just... | Read more »
The Witness (Games)
The Witness 1.0 Device: iOS Universal Category: Games Price: $9.99, Version: 1.0 (iTunes) Description: You wake up, alone, on a strange island full of puzzles that will challenge and surprise you. You don't remember who you are, and... | Read more »
Egg, Inc. guide - how to build your gold...
Egg, Inc.'s been around for some time now, but don't you believe for one second that this quirky clicker game has gone out of style. The game keeps popping up on Reddit and other community forums thanks to the outlandish gameplay (plus, the... | Read more »

Price Scanner via MacPrices.net

Sunday sale: 13-inch 3.1GHz MacBook Pros for...
Amazon has 2017 13″ 3.1GHz MacBook Pros on sale today for up to $150 off MSRP, each including free shipping: – 13″ 3.1GHz/256GB Space Gray MacBook Pro (MPXV2LL/A): $1649.99 $150 off MSRP – 13″ 3.1GHz... Read more
Looking for a 2017 12″ Retina MacBook? Save $...
Apple has Certified Refurbished 2017 12″ Retina MacBooks available for $200-$240 off the cost of new models. Apple will include a standard one-year warranty with each MacBook, and shipping is free.... Read more
Apple Offering Up To $455 Credit Toward iPhon...
iPhone 8 and 8 Plus are now available at the Apple Store, and you can receive up to $375 credit toward a new iPhone purchase when you trade in your eligible smartphone. Photo Courtesy Apple Just... Read more
AnyTrans Offers iOS Users Three Ways For Movi...
iMobie Inc. today announceed AnyTrans v6.0.1, which now can help iOS users move all data to iPhone 8/8 Plus seamlessly. The software is available both on Mac and Windows and fully able to move all... Read more
Snag a 13-inch 2.3GHz MacBook Pro for $100 of...
B&H Photo has 2017 13″ 2.3GHz MacBook Pros in stock today and on sale for $100 off MSRP, each including free shipping plus NY & NJ sales tax only: – 13-inch 2.3GHz/128GB Space Gray MacBook... Read more
Verizon offers new iPhone 8 for $100-$300 off...
Verizon is offering the new iPhone 8 for up to $300 off MSRP with an eligible trade-in: • $300 off: iPhone 6S/6S Plus/7/7 Plus, Google Pixel XL, LG G6, Moto Z2 Force, Samsung Galaxy S7/S7 edge/S8/S8... Read more
Apple Refurbished 2017 13-inch MacBook Pros a...
Apple has Certified Refurbished 2017 13″ Touch Bar MacBook Pros in stock today and available for $200-$300 off MSRP. A standard Apple one-year warranty is included with each MacBook, and shipping is... Read more
OWC USB-C Travel Dock with 5 Ports Connectivi...
OWC have announced the new OWC USB-C Travel Dock, the latest addition to their line of connectivity solutions. The USB-C Travel Dock lets you connect its integrated USB-C cable to a Mac or PC laptop... Read more
Pelican Products, Inc. Unveils Cases For All...
Pelican Products, Inc. has announced the launch of its full line of cases including Voyager, Adventurer, Protector, Ambassador, Interceptor (for the Apple iPhone 8 and 8 Plus backwards compatible... Read more
$100 off new 2017 13-inch MacBook Airs
B&H Photo has 2017 13″ MacBook Airs on sale today for $100 off MSRP including free shipping. B&H charges NY & NJ sales tax only: – 13″ 1.8GHz/128GB MacBook Air (MQD32LL/A): $899, $100 off... Read more

Jobs Board

Development Operations and Site Reliability E...
Development Operations and Site Reliability Engineer, Apple Payment Gateway Job Number: 57572631 Santa Clara Valley, California, United States Posted: Jul. 27, 2017 Read more
Development Operations and Site Reliability E...
Development Operations and Site Reliability Engineer, Apple Payment Gateway Job Number: 57572631 Santa Clara Valley, California, United States Posted: Jul. 27, 2017 Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Instructional Designer, *Apple* Product Doc...
Job Summary The Apple Product Documentation team is looking for an instructional designer or a video editor to write user documentation for its professional video Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.