Sven Barth wroteHello together!
Since revision 36105 FPC now supports the use of array constructorsusing the "[...]" syntax inside ordinary code blocks like Delphi doessince - I think - XE8. And yes, even nested ones are supported (take alook at $fpcdir/tests/test/tarrconstr5.pp for a bit of inspiration).
Considering that this changed how "[...]" is handled I'd like you all totest whether your existing code still works (especially if it's dealingwith sets!) and to try this new feature to see if there are any problemsthat our testsuite doesn't cover yet.
If you report bugs, then please attach the tag "array constructors".
Ah yes, /very/ nice :-)
I append a chunk of fun code, which as it stands needs separate functions per rank (i.e. for 1 dimension, 2 dimensions and so on). Can these be rationalised using generics?
Output should look something like
a3:
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
5 6 7 8 9
1 3 5 7 9
2 4 6 8 0
+/ a3:
6 8 10 12 14
2 5 8 11 14
3 6 9 12 5
a2:
6 8 10 12 14
2 5 8 11 14
3 6 9 12 5
+/ a2:
11 19 27 35 33
a1:
11 19 27 35 33
+/ a1:
125
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]
program testReduction;
{$mode objfpc}{$H+}
// This demo program abuses FPC's custom operator facility to simulate
// Vector Pascal's \+ (reduce-add) operator, which is derived from APL's
// +/ function/operator.
// It's reasonable to expect no sane code to try to attempt to add a
// procedure to an array or a number.
type TReduce= procedure(p1: pointer);
const Reduce: TReduce= nil;
type t1= array of longint;
t2= array of t1;
t3= array of t2;
{$MACRO ON}
{$DEFINE SHOW_IDENTITY:=// WriteLn('Identity:'); print(result); WriteLn; }
procedure print(i: longint);
begin
Write(i)
end { print } ;
procedure print(const a: t1);
var i: integer;
begin
for i := Low(a) to High(a) do
Write(a[i], ' ');
WriteLn
end { print } ;
procedure print(const a: t2);
var i: integer;
begin
for i := Low(a) to High(a) do
print(a[i]);
WriteLn
end { print } ;
procedure print(const a: t3);
var i: integer;
begin
for i := Low(a) to High(a) do
print(a[i]);
// WriteLn('-----');
WriteLn
end { print } ;
operator + (const a1, a2: t1): t1;
var i: integer;
begin
SetLength(result, Length(a1));
for i := Low(a1) to High(a1) do
result[i] := a1[i] + a2[i]
end { + } ;
operator + (const a1, a2: t2): t2;
var i: integer;
begin
SetLength(result, Length(a1));
for i := Low(a1) to High(a1) do
result[i] := a1[i] + a2[i]
end { + } ;
const additiveIdentity= 0;
multiplicativeIdentity= 1;
operator + (const r: TReduce; const a: t1): longint;
var i: integer;
begin
result := additiveIdentity;
SHOW_IDENTITY
for i := Low(a) to High(a) do
result += a[i]
end { + } ;
operator + (const r: TReduce; const a: t2): t1;
var i: integer;
begin
SetLength(result, Length(a[Low(a)]));
for i := Low(result) to High(result) do
result[i] := additiveIdentity;
SHOW_IDENTITY
for i := Low(a) to High(a) do
result += a[i]
end { + } ;
operator + (const r: TReduce; const a: t3): t2;
var i: integer;
function additiveIdentityArray1: t1;
var i: integer;
begin
SetLength(result, Length(a[0, 0]));
for i := Low(result) to High(result) do
result[i] := additiveIdentity
end { additiveIdentityArray1 } ;
begin
SetLength(result, Length(a[Low(a)]));
for i := Low(result) to High(result) do
result[i] := additiveIdentityArray1;
SHOW_IDENTITY
for i := Low(a) to High(a) do begin
result += a[i]
end
end { + } ;
var a0: longint;
a1: t1;
a2: t2;
a3: t3;
begin
a3 := [[[1,2,3,4,5],[1,2,3,4,5],[1,2,3,4,5]],
[[5,6,7,8,9],[1,3,5,7,9],[2,4,6,8,0]]];
WriteLn('a3:');
print(a3);
WriteLn('+/ a3:');
a2 := reduce + a3;
print(a2); WriteLn;
WriteLn('a2:');
print(a2);
WriteLn('+/ a2:');
a1 := reduce + a2;
print(a1); WriteLn;
WriteLn;
WriteLn('a1:');
print(a1);
WriteLn('+/ a1:');
a0 := reduce + a1;
WriteLn(a0);
WriteLn
end.
