2021-11-14 | Paul Boddie | file changeset files shortlog | Introduced copyable and mutable flags in the tagged region of attribute values. Such flags are set when new integer and floating point values are created, but the mutable flag is cleared when such attributes are propagated between functions in order to prevent values being replaced upon assignment to parameter names, this being a concern when value copying is introduced. | tagged-address-values |
paul@2 | 1 | def f(): |
paul@2 | 2 | l = [1, 2, 3] |
paul@2 | 3 | x = l |
paul@2 | 4 | a, b, c = l |
paul@2 | 5 | d, e, f = [1, 2, 3] |
paul@243 | 6 | print a, b, c # 1, 2, 3 |
paul@243 | 7 | print d, e, f # 1, 2, 3 |
paul@243 | 8 | print x # [1, 2, 3] |
paul@2 | 9 | |
paul@2 | 10 | def g(x): |
paul@2 | 11 | l = [1, 2, 3] |
paul@2 | 12 | m = [4, l, 6] |
paul@2 | 13 | if x: |
paul@2 | 14 | n = l |
paul@2 | 15 | else: |
paul@2 | 16 | n = m |
paul@173 | 17 | print n |
paul@2 | 18 | |
paul@560 | 19 | def h(): |
paul@560 | 20 | return 7, 8, 9 |
paul@560 | 21 | |
paul@561 | 22 | def i(): |
paul@561 | 23 | a, b, c = h() |
paul@561 | 24 | print a, b, c |
paul@561 | 25 | |
paul@561 | 26 | # Test assignment operations within functions. |
paul@561 | 27 | |
paul@197 | 28 | f() |
paul@243 | 29 | g(0) # [4, [1, 2, 3], 6] |
paul@243 | 30 | g(1) # [1, 2, 3] |
paul@197 | 31 | |
paul@561 | 32 | # Test aliasing, assignment of list elements and direct assignment of elements. |
paul@561 | 33 | |
paul@2 | 34 | l = [1, 2, 3] |
paul@2 | 35 | x = l |
paul@2 | 36 | a, b, c = l |
paul@2 | 37 | d, e, f = [1, 2, 3] |
paul@560 | 38 | |
paul@560 | 39 | print a, b, c # 1 2 3 |
paul@560 | 40 | print d, e, f # 1 2 3 |
paul@243 | 41 | print x # [1, 2, 3] |
paul@560 | 42 | |
paul@561 | 43 | # Test embedding of sequences in sequences. |
paul@561 | 44 | |
paul@2 | 45 | m = [4, l, 6] |
paul@561 | 46 | |
paul@561 | 47 | # Test sequence truth value interpretation. |
paul@561 | 48 | |
paul@2 | 49 | if x: |
paul@2 | 50 | n = l |
paul@2 | 51 | else: |
paul@2 | 52 | n = m |
paul@560 | 53 | |
paul@243 | 54 | print n # [1, 2, 3] |
paul@560 | 55 | |
paul@561 | 56 | # Test temporary variable usage at module level. |
paul@561 | 57 | |
paul@560 | 58 | a, b, c = h() |
paul@560 | 59 | print a, b, c # 7 8 9 |
paul@561 | 60 | |
paul@561 | 61 | # Test temporary variable usage in functions. |
paul@561 | 62 | |
paul@561 | 63 | i() # 7 8 9 |
paul@561 | 64 | |
paul@561 | 65 | # Test temporary variable usage in classes. |
paul@561 | 66 | |
paul@561 | 67 | class C: |
paul@561 | 68 | a, b, c = h() |
paul@561 | 69 | print a, b, c # 7 8 9 |