We are close to a future in which everyone can and will program. Whether it is some Javascript, some R or an extensive spreadsheet, programming happens everywhere. What do end-users do in the wild? And what can we learn from that as programming language designers? In this talk Felienne will summarize her research on the topic of end-user testing, error finding and refactoring, as well as presenting a sneak peek into the future of her research as Delft University.

1. Small, Simple & Smelly:
What we can learn from
examining end-user artifacts?

2. Ehm?
DSLs and End-Users?

3. Ehm?
DSLs and End-Users?

4. Ehm?
DSLs and End-Users?

5. “In the future, everyone will be a
programmer for 15 minutes”

8. Internet

9. The web

10. YouTube

11. “In the future, everyone will be a
programmer for 15 minutes”

16. was 44%
10 years ago

18. Spreadsheets are code

24. Spreadsheets live
5 years on average

25. Are used by
12 different people

27. Spreadsheets are code
Similar activities, power and problems

29. How to help everyone?

35. “Long method”

36. “Too many
parameters”

41. 42% of spreadsheets
have smells
Detecting and Refactoring Code Smells in Spreadsheet Formulas, Herman
Empirical Software Engineering, 2014

42. What are the tools needed to
make this prediction true?
Maybe smell detection
is a good tool....?

45. The Scratch programming language

46. The Scratch programming language

48. Scripts

49. Each sprite can
have scripts

52. One ‘good’
version

53. Two ‘smelly’
versions

54. Two ‘smelly’
versions
Long method Duplicated code

55. Version N

56. Version D

57. Version D

58. Version D

59. Version D

60. Version D

61. Version D

62. Version N

63. Version N

64. Version L

65. Do code smells
matter to kids?

66. tl;dr
Yes

67. tl;dr
Yes
Kids performed
significantly better
on the non-smelly
program

68. tl;dr
Yes
But, differences tasks are impacted differently

69. Let’s take a
closer look!

70. Version N
“When have
you won the
game?”

71. Version L
“When have
you won the
game?”

72. Let’s take a
closer look!

73. Version N
“Make the
game go to 10
points”

74. Version N
“Make the
game go to 10
points”

75. Version D

76. Version D

77. Version D

78. Let’s take a
closer look!

80. Are smells
common?

86. How do kids
code in
Scratch?

91. Available on GitHub!
https://github.com/TUDelftScratchLab/ScratchDataset

92. How do kids
code in
Scratch?

104. 1 2
3 4

105. 3
1 2
4

106. 3
1 2
4
24
%
1%
8%
24
%

107. 3
1 2
4
24
%
1%
8%
24
%
Any: 28% of the projects

111. Now what?

113. Educate!

115. Education is
possible!

117. 0
50
100
150
200
250
300
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Numberofstudents
Age

118. What kids thought
they learned

119. What they
really learned

120. *Paper Under Review

122. *http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141357
Meet
Dr. Pigeon

123. *http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141357
Meet
Dr. Pigeon

124. *http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141357
Meet
Dr. Pigeon
75% correct
after 2 weeks

125. Sparrow Decks

126. Sparrow Decks

135. Now:
• Q&A
Then:
• Hands on!!
“In the future, everyone will be a
programmer for 15 minutes”

136. More info?
• www.felienne.com
• github.com/TUDelftScratchLab
Want to connect?
• mail@felienne.com
“In the future, everyone will be a
programmer for 15 minutes”

139. What are the tools needed to
make this prediction true?

140. What are the tools needed to
make this prediction true?