June 2018 Update

Task/Arrays/HolyC/arrays-1.holyc

@@ -0,0 +1,8 @@
+// Create an array of fixed size
+U8 array[10] = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10;
+
+// The first element of a HolyC array is indexed at 0. To set a value:
+array[0] = 123;
+
+// Access an element
+Print("%d\n", array[0]);

Task/Arrays/HolyC/arrays-2.holyc

@@ -0,0 +1,98 @@
+record aThing(a, b, c)       # arbitrary object (record or class) for illustration
+
+procedure main()
+    A0 := []                 # empty list
+    A0 := list()             # empty list (default size 0)
+    A0 := list(0)            # empty list (literal size 0)
+
+    A1 := list(10)           # 10 elements, default initializer &null
+    A2 := list(10, 1)        # 10 elements, initialized to 1
+
+    # literal array construction - arbitrary dynamically typed members
+    A3 := [1, 2, 3, ["foo", "bar", "baz"], aThing(1, 2, 3), "the end"]
+
+    # left-end workers
+    # NOTE: get() is a synonym for pop() which allows nicely-worded use of put() and get() to implement queues
+    #
+    Q := [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+    x := pop(A0)        # x is 1
+    x := get(A0)        # x is 2
+    push(Q,0)
+    # Q is now [0,3, 4, 5, 6, 7, 8, 9, 10]
+
+    # right-end workers
+    x := pull(Q)        # x is 10
+    put(Q, 100)         # Q is now [0, 3, 4, 5, 6, 7, 8, 9, 100]
+
+    # push and put return the list they are building
+    # they also can have multiple arguments which work like repeated calls
+
+    Q2 := put([],1,2,3)    # Q2 is [1,2,3]
+    Q3 := push([],1,2,3)   # Q3 is [3,2,1]
+    Q4 := push(put(Q2),4),0] # Q4 is [0,1,2,3,4] and so is Q2
+
+    # array access follows with A as the sample array
+    A := [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]
+
+    # get element indexed from left
+    x := A[1]           # x is 10
+    x := A[2]           # x is 20
+    x := A[10]          # x is 100
+
+    # get element indexed from right
+    x := A[-1]          # x is 100
+    x := A[-2]          # x is 90
+    x := A[-10]         # x is 10
+
+    # copy array to show assignment to elements
+    B := copy(A)
+
+    # assign element indexed from left
+    B[1] := 11
+    B[2] := 21
+    B[10] := 101
+    # B is now [11, 21, 30, 50, 60, 60, 70, 80, 90, 101]
+
+    # assign element indexed from right - see below
+    B[-1] := 102
+    B[-2] := 92
+    B[-10] := 12
+    # B is now [12, 21, 30, 50, 60, 60, 70, 80, 92, 102]
+
+    # list slicing
+    # the unusual nature of the slice - returning 1 less element than might be expected
+    # in many languages - is best understood if you imagine indexes as pointing to BEFORE
+    # the item of interest. When a slice is made, the elements between the two points are
+    # collected. eg in the A[3 : 6] sample, it will get the elements between the [ ] marks
+    #
+    # sample list:              10  20 [30  40  50] 60  70  80  90  100
+    # positive indexes:        1   2   3   4   5   6   7   8   9   10  11
+    # non-positive indexes:  -10  -9  -8  -7  -6  -5  -4  -3  -2  -1   0
+    #
+    # I have deliberately drawn the indexes between the positions of the values.
+    # The nature of this indexing brings simplicity to string operations
+    #
+    # list slicing can also use non-positive indexes to access values from the right.
+    # The final index of 0 shown above shows how the end of the list can be nominated
+    # without having to know it's length
+    #
+    # NOTE: list slices are distinct lists, so assigning to the slice
+    # or a member of the slice does not change the values in A
+    #
+    # Another key fact to understand: once the non-positive indexes and length-offsets are
+    # resolved to a simple positive index, the index pair (if two are given) are swapped
+    # if necessary to yield the elements between the two.
+    #
+    S := A[3 : 6]       # S is [30, 40, 50]
+    S := A[6 : 3]       # S is [30, 40, 50]   not illegal or erroneous
+    S := A[-5 : -8]     # S is [30, 40, 50]
+    S := A[-8 : -5]     # S is [30, 40, 50]   also legal and meaningful
+
+    # list slicing with length request
+    S := A[3 +: 3]      # S is [30, 40, 50]
+    S := A[6 -: 3]      # S is [30, 40, 50]
+    S := A[-8 +: 3]     # S is [30, 40, 50]
+    S := A[-5 -: 3]     # S is [30, 40, 50]
+    S := A[-8 -: -3]    # S is [30, 40, 50]
+    S := A[-5 +: -3]    # S is [30, 40, 50]
+end

Task/Arrays/HolyC/arrays-3.holyc

@@ -0,0 +1,3 @@
+# Unicon provides a number of extensions
+# insert and delete work on lists allowing changes in the middle
+# possibly others