Types of Programming Languages, Translators and Integrated Development Environments (IDEs) (Copy)

• Computers can only understand machine code, which is in binary form of 1 and 0.
• A program written in a programming language must be translated to machine code to ensure that the computer can understand it.
• We tell computer through program on what to do, how to do and when to do it.
• Through programs, a computer can perform multiple tasks.
• Computer program
  • A list of instructions that enables a computer to perform specific tasks.
  • Can be written in high-level languages and low-level languages
  • Most programmers use high level languages

High Level Languages and Low-Level Languages

• High Level Languages
  • Here, the main focus is on the problem solved.
  • No real understanding required of the hardware or instruction set of the computer.
  • High-level languages are portable and can be used on different types of computers
  • Designed with the programmer in mind.
  • Easier statements that can make coding easier
    • Language is closer to English
    • Shorter time
    • Debugging during development
    • Can be maintained during use.
  • Many different examples such as Delphi, Java, Pascal, Visual Basis, C++, Python and many more.
  • If you learn one high level language, it becomes easier to learn other high level languages.
  • Problem-oriented
• Low level languages
  • Focused on specific architecture and hardware of a particular type of computer
  • Can refer to machine code or assembly language
  • Machine Code
    • It is difficult to understand and storage and manipulation of data can be complicated.
    • Usually written in hexadecimal.
• Benefits and Drawbacks
  • High Level Languages
    • Advantages
      • Can be used on multiple computers
      • Easier to understand
      • Quicker to use
      • Easier to debug
      • Maintenance during use is easy
    • Disadvantages
      • Larger programs with more space
      • Longer to execute
      • May not be able to use special hardware
  • Low-Level
    • Advantages
      • Use special hardware
      • Machine-dependent instructions
      • Not much space taken in primary memory
      • Tasks performed very quickly
    • Disadvantages
      • Longer to write and debug
      • Difficult to understand

Assembly Language

• LDA means load value of the variable into the accumulator
• ADD means add value of variable to the value stored in accumulator
• STO means replace the value of the variable by the value stored in the accumulator
• Assembly language needs to be translated into machine code using an assembler to run.

Translators

• Computer can only understand programs when they are translated to binary instructions and machine code.
• Done by translator
• Different translator programs perform different tasks
• Compiler
  • Translates the entire program written in HLL into machine code in one go
  • The program produced can be directly used by computer to perform the required task
  • Once compiled, the same program can be used again and again to perform the same task
    • Recompilation not required
  • If any errors occur, the error report is produced instead of the compiled program
  • Produces executable file
  • One high level language statement can be translated into several machine code instructions
  • Distributed to general use
• Interpreters
  • Reads a statement from the program, translates it, performs the specified action and then goes on to the next statement, repeating the process.
  • If an error is present in a statement, the execution stops
  • Error message is given, with sometimes a suggested correction
  • Need to reinterpret program each time it is used.
  • One high-level language program statement may require several machine code instructions to be executed
  • Usually used during development of program
• Assembler
  • Translates a program from assembly language into machine code.
  • Can be used directly by the computer
  • Once assembled, re-assembly not required
  • Can be used again and again.
  • Produces executable file
  • One low-level language statement is usually translated into one machine code instruction
  • Distributed to general use
• Integrated Development Environment
  • IDE
  • Used when writing a computer program
  • A software that provides an editor to enter and amend the code
  • Auto-completion where the command being written is provided a suggested end
  • Auto-correction: where the spelling of a command are told the correct one
  • Prettyprint changes the colors of the words to different identifiers
  • Block minimizing so different sections of the code can be minimized and read easily.
  • Relevant translators included as well
  • Run-time environment
    • Output is displayed
    • Command line or GUI both can be possible based on the programming language and the programming code.
• Debugging features
  • Error diagnosis
  • Helps to find the problems
  • Break points: Code stops at these points defined by the user.
    •  Can check the output of a code to a certain point.
  • Variable watch windows can show the value of the variables of the code to be seen while being types
  • Stepping
    • Run one line at a time to determine if each line is correct