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Quick Reference

For people who already know how to program with some other languages and do not want to go through the complete Small Basic tutorials, here is a short example that contains most language constructs and a short explanation of each. You can copy this program into Small Basic for testing. This example will not run directly on the EV3 brick, because it uses the Small Basic text window.
  ' Demo program explaining most of Small Basic
  ' (all comments start with single quotation mark)

  ' Execution starts here
  A = 5       ' variables are implicitly declared at first use 
  a = a + 1   ' everything is case-insensitive
  B[a] = 55   ' arrays are implicitly defined and grow as needed
  X = "hi"    ' variables can also hold text

  Sub write   ' defines a sub-program with this name (no parameters possible)
    TextWindow.WriteLine(X) 
                            ' call library function, access variable defined elsewhere
  EndSub
     ' control flow of the main program runs around the Sub - definitions

  TextWindow.WriteLine("A="+a) ' string concatenation with +
  WRITE()             ' call subprogram. name is also case-insensitive
  write2()            ' may call subprogram that is defined further down the code

  TextWindow.Writeline("B[6]="+B[6])  ' access to arrays
  
  For i=2 to 5 		      	  ' a loop from 2 to 5 (inclusive)
	TextWindow.Writeline("I:"+I)
  EndFor
  For i=6.5 to 10.5 step 2        ' a loop with fractional values and larger step
	TextWindow.Writeline("I:"+I)
  EndFor

  Sub write2
	write()          ' subprogram can call other subprograms
	write()
  EndSub
     ' control flow of the main program runs around the Sub - definitions

   I=99		' case insensitive - overwrites previous i
   while i>3    ' loop with condition
     i=i/2
     TextWindow.Writeline("I:"+i)
   endwhile
   TextWindow.WriteLine("PI="+Math.PI)
              ' a library property (access without parentheses)
   TextWindow.WriteLine("SIN="+Math.Sin(0.5))  
                           ' library function returning value

   A=50
   B=20
   If a<5 then	' an IF-construct with multiple conditions
	TextWindow.WriteLine("first")
   elseif a<10 and b<100 then          ' logic 'and' of conditions
	        TextWindow.WriteLine("second")
   elseif a<20 or (b>40 and b<60) then ' logic 'or' and nested conditions
	TextWindow.WriteLine("third")
   else
	TextWindow.WriteLine("other")
   endif
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