Logic and Language

Logic and Language

1. Validations

   • range check
     • a number or date is within a sensible / allowed range
   • type check
     • data is of the right type, such as integer, letter or text
   • length check
     • text entered is not too long or too short - for example, a password is between 8 and 15 characters
   • presence check
     • checks that data has been entered, i.e. the field has not been left black
   • format check
     • checks that the format of, for example, a postcode or email address is correct

2. IDE

   • they have number of tools and features that help programmers when they are programming
     • line number
       • allow a programmer to clearly see each line of code
     • syntax highlighting
       • the colour of the text changes to show different parts of the program
     • error diagnostics
       • it help a programmer to find where they have made a mistake
     • debugging code
       • breakpoints
         • it is set by the programmer so that the IDE stops the program mid-way through running
         • they can step through code line by line
     • run- time environment
       • allows a programmer to test their program while it is running

3. truth table

   • purpose of truth table
     • it shows all the possible input and associated output