Learning programming practice and programming theory in the computer laboratory

Figures & data

Table 1. The table summarises key points of the analysis regarding the interaction between theory-oriented and practice-oriented actions that occurred in Episode A.

Theory-oriented action	Practice-oriented action
A.1 Bill reads the lab instruction document where the ‘if’-statement is explained and examples are given.
A.2-3 How often … ? Should we use it after ‘if’ too?
	A.4-6 Bill types ‘{‘ directly after ‘if’. Later he makes a new line after the first ‘System.out’ statement and types ‘}’ on the new line.
A.7 Celia: I would have put it before the ‘if’ so ‘if’ kind of comes inside.
	A.8 Adam: They don’t do it like that there.
	A.9-10 Bill: Ops, it shouldn’t be there, it should be here. [Moves ‘{‘ to the end of the first line ‘if(…);’]
A.11 Celia: Why did we put it there?
	A.12 Bill writes ‘{’ after ‘else’
	A.13 Adam: Because they did it like that.
A.14 Celia: But why do you do like that? […] I imagine that it should be like, well, parentheses you kind of do first.
	A.15 [Bill types ‘}’ after the final ‘System.out’ statement.]
A.16-19 No it’s not parenthesis […] what is it really? […] This is kind of the method that is included in ‘if’. […]

Table 2. The table summarises key points of the analysis regarding the interaction between theory-oriented and practice-oriented actions that occurred in Episode B.

Theory-oriented action	Practice-oriented action
	B.1. [David writes ‘public’]
	B.2. David: Should we make an int?
B.3. Erica: But do we need to make an int? It won’t come out a number, it should, yes.
	B.4. David: Ehh, or?
B.5. Erica: We will let in a number. But then you perhaps don’t need an int before?
	B.6. David: Don’t know.
B.7. Erica: It should only run now.
	B.8. [David reads the description of the assignment in the lab instruction: ‘Write a method void drawCircle(int radius)’]
	B.9. David: It should be void, ok [types ‘void’. Now it says ‘public void’ on the screen.]
B.10. Erica: What does void mean again? I forget. B.11. David: [Sighs] Yes what is void now again. I think void means that it doesn’t … B.12. Erica: It doesn’t print anything [snaps her fingers] B.13. David: It doesn’t print anything …
B.14. Erica: Bang, it just do something, that’s it. B.15. David: Hm, right, it doesn’t expect anything … It shouldn’t be an answer. B.16. Erica: but it should just do something.
	B.17. David: And it should be called drawCircle [types and talks] B.18. [David types ‘drawCircle(int radius)’ which makes the method head ‘public void drawCircle(int radius)’]

Table 3. The table summarises key points of the analysis regarding the interaction between theory-oriented and practice-oriented actions that occurred in Episode C.

Theory-oriented action	Practice-oriented action
	C.1. [David presses enter after typing ‘if (y < j) {;’] C.2. [David types on the new line: ‘int a’]
C.3. Erica: Do you have to have a new line after ‘else’? C.4. David: How do you mean? C.5. Erica: Well we write ‘int’ beneath as we did for the ‘if’, kind of.
C.6 David: I guess it’s not necessary, or it should interpret that since, it should interpret everything inside the braces as one thing. C.7 Erica: Yes. C.8 David: I believe. It shouldn’t make any difference between that and that. C.9 Erica: No. C.10 David: Or maybe it does.

Figure 1. The example has the following explanation: ‘It is important that the type of the value in the return-statement aligns with the type in the method head! Since the sqrt-method returns a value of type double, in the right method we have to explicitly convert the value to an int.’ (translated from Swedish).