93 lines
2.2 KiB
Markdown
93 lines
2.2 KiB
Markdown
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# Finishing touches!
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Now you have a perfectly working counter program! For your final lesson however, we will teach you about comments and explicitly exiting the program!
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## New operations
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* `:0(comment)`, comment, an operation that does nothing but is helpful for a programmer!
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* `:~`, exit, explicitly calls an exit to your program
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* `:*(left),(right),(output)`, string concatenation, concatenates `(left)` and `(right)` and stores it in `(output)`
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## Tutorial
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Your program should look something like this:
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```
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:>"Enter some numbers!",message
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:!message
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:?starting_number
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:?finishing_number
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:?step
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:@count
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:astarting_number,step,starting_number
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:!starting_number
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:-count,starting_number,finishing_number
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```
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This program is perfectly readable, however it could do with some comments and an obvious exit point!
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You can add comments as an operation and it wont affect your program! So you could do something like this!
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```
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:>"Enter some numbers!",message
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:!message
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:0 Prompt the user for their chosen numbers!
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:?starting_number
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:?finishing_number
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:?step
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:0 Keep counting until we hit the finishing number
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:@count
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:astarting_number,step,starting_number
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:!starting_number
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:-count,starting_number,finishing_number
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:0 We're done! Quit!
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:~
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```
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We can also add a concatenation! Before the explicit exit, initialise the variable `msg` with the string `"I have counted to "`! After this operation, add the operation `:*msg,finishing_number,msg` and print out message!
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Now when your program finishes, it will tell you what your program counted to!
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Now your output will look like this if you run your program!
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```
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Enter some numbers!
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? 0
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? 5
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? 1
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1
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2
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3
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4
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5
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I have counted to 5
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```
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## Continue the guidebook
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Well done! You've finished the guidebook!
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You can further your learning by going to the further concepts section on the top navigation bar!
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## After example
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```
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:>"Enter some numbers!",message
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:!message
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:0 Prompt the user for their chosen numbers!
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:?starting_number
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:?finishing_number
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:?step
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:0 Keep counting until we hit the finishing number
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:@count
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:astarting_number,step,starting_number
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:!starting_number
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:-count,starting_number,finishing_number
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:0 We're done! Quit!
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:>"I have counted to ",msg
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:*msg,finishing_number,msg
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:!msg
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:~
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```
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