SD notes Part 2

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					Hamilton Grammar School ICT Department

Software Development Languages & Environments
Learning Criteria & Self Evaluation 2008 - 2009 Higher Computer Software Student Name: __________________________
Complete the smiley or colour it in - for each bit of information in this book (but only for the pages you are told to read)

I know exactly what this means and can explain it

I know what this means but I find it hard to explain

I don’t know at all what this means Help Me Please!

Hamilton Grammar School
ICT Department Higher Computing

Learning Criteria & Self Evaluation Types of Programming Language Procedural (imperative) – Concise list of instructions are given in the correct sequence to solve problems Uses variables Uses sequence, selection & iteration Uses procedures (subprograms) Uses parameters – Pascal, COBOL, BASIC, COMAL, C++ Declarative – States what has to be solved – no solution only facts Uses a Knowledge base to hold facts & Rules Uses Recursion to do iteration (loops) Uses Queries to search for answers – Prolog Event-Driven Used with GUI’s Graphical objects have code linked to them. Clicking on these objects runs the event (program) linked to that bit of code.


Visual Basic, Delphi, Hypertalk

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Hamilton Grammar School
ICT Department Higher Computing

Learning Criteria & Self Evaluation Scripting Commands used to tailor or customise tasks/functions within applications. Uses commands from within apps package. Can be created using a macro

– Visual Basic for Applications (VBA),Javascript, Perl Macro – A macro is created by recording the keystrokes/instructions to create the script - a single button/command is entered to activate the code. A Translator is required to convert a high level language to machine code Interpreter – translates one line (at a time) of a high level language to machine code then executes it – very good for debugging as code stops precisely where the error occurs – only the program and interpreter is required Compiler Translates the whole high level language program in one go – Three files are required; Source code – original high level language code. Compiler – program that creates machine code version from source code. Object code – the final machine code version of the original HLL. Page 3

Hamilton Grammar School
ICT Department Higher Computing

Learning Criteria & Self Evaluation Differences Compiled code runs faster than translated code as each line is only translated once regardless of the number of times it is repeated. Compiled code is more difficult to debug Users using a compiled program only get the object code version ( harder to hack). – Some languages are developed using interpreters then compiled to improve speed. Module Libraries (part of software library.) – A collection of procedures (modules) already created and saved that can be loaded into new programs when required. – Save time in; Design – already done when creating module Implementation – only needs loaded and adapted Testing – all modules already tested Documentation – already fully documented

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