isbn9789526046266

Table A.1 continued
No. Topic Description Source
49 Calls When the value of a global variable is changed in a
procedure, the new value will not be available to the main
program unless it is explicitly passed to it.
50 Calls A function (always) changes its input variable to become
the output.
Fleury (1991)
Paz and Leron (2009)
51 Calls Expressions (not their values) are passed as parameters. local
52 Calls Argument expressions cause changes in existing variables. George (2000a)
53 Calls Upon return, the value of a variable changes to correspond
to match a previously given parameter.
George (2000a)
54 Rec Null model of recursion: recursion is impossible. Kahney (1983)
55 Rec Active model: only the ‘active aspect’ of recursion
understood, not return values.
Götschi et al. (2003)
56 Rec Step model: single- or two-step recursion, but no more. Götschi et al. (2003)
57 Rec Return value model: each instantiation first produces a
value, before the next one is started; then all values are
combined to get the result
58 Rec Passive model: active part not understood, only the
combinatorics of the return values.
59 Rec Recursion is merely a programming construct used as a
template in certain kinds of programs; runtime behavior is
‘magic’.
Götschi et al. (2003)
Sanders et al. (2006)
Booth (1992); Kahney (1983);
Götschi et al. (2003)
60 Rec Recursion is perceived as an algebra problem. Götschi et al. (2003)
61 Rec Looping model of recursion (single-instantiation); recursion
is merely a construct for producing repetition, not
understood as self-reference.
62 Refs Even primitive values (in Java) are handled through
references.
63 Refs The variables for storing and assigning primitive values are
fundamentally different from the variables used for storing
objects (in Java).
64 Refs A variable associated with an object is merely a name which
can be used to manipulate an object or ’thing’ in a program.
65 Refs A (non-primitive Java) variable does not hold a reference
but a set of object properties.
66 Refs Assigning an object means ‘sending’ an object (or a copy)
to a variable.
Kahney (1983); Bhuiyan et al.
(1990); Götschi et al. (2003);
Booth (1992)
Sorva (2008)
Sorva (2008)
Sorva (2008); Ma (2007)
Sorva (2008); Ma (2007)
Ma (2007)
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