That makes me think, "How, straight with C++, do we teach programming language to someone who never knows progamming language?"
I mean like your quote before Phinds.
program MyFirstProgram;
{ all variables here }
{ all goto Labels here }
begin
{ all the instructions here }
end.Good steps.
"Nothing can accomplish it" A very good phrase for pointer introduction. I remember, 20 years ago I used to teach programming language when I was in college for some cash. Just fire the pointer away.
As I recall from many years ago, BASICA (and GWBASIC and several other variants of BASIC) had subroutines (called with GOSUB) and functions.
Stephanus said:
Nope, that isn't Pascal. For assignment, you use := .
Your first MOV instruction is missing something.Stephanus said:
Sorry, you have sharp eye, Mark!
var
A,B,C: Word;
begin
A:=B+C;
{ assembly equivalence
mov AX,[B]
add AX,[C]
mov [A],AX
}
end.var
A: Integer;
B: Word;
begin
B:=A; //works
asm
mov AX,A // syntax error
end;
end;What bad idea? Using GOTO or go straight to assembly after BASIC?
But I find BASIC is very useful to teach someone the first programming language.
Couldn't agree more. NO GOTO, GOSUB. At least not GOSUB. Switch to Pascal before GOSUB.
Why Pascal? I might be wrong, but as far as I know it's pretty much a dead language. After doing a little searching, I find that it still exists, though, as Delphi, which Borland sold off in 2008 to a company named Embarcadero.
Although the use of goto often leads to unreadable "spaghetti" code, and was excoriated in a paper by Edsger Dijkstra in 1968, its use is recommended in certain instances, such as for "end-of-function error handlers and for multi-level breaks from loops." -- Per Dennis Ritchie and Brian Kernighan from wiki article in link below.
Borland made a great marketing decision back when they released TurboPascal in 1983. As I recall, it sold for $49 (?), and they sold a ton of copies, and got a lot of people interested in programming. Back about '83 or so I had a version of UCSD Pascal that ran on Apple II computers. After I started learning C in '85, I was all done with Pascal.
Well, it still exists, and you do not have to pay for it. Using google turned up this link in a second: http://www.gnu-pascal.de/gpc/h-index.html. Some additional info is here: https://en.wikipedia.org/wiki/GNU_Pascal.
Aside from Borland text editor which allow cursor to go up/down vertically
, what I like about Pascal is its nested procedure.procedure Level1;
var
A: Integer;
procedure Level2;
procedure Level3;
begin
A:=10; { don't have to put A in global scope }
end;
begin
end;
begin
end;constructor Square.InitSquare;
begin
A:-10;
B:=20;
{ some codes here }
InitRectangle; { call the inherited constructor after some lines processed }
end;GOTO is important for an experienced programmer. For a beginner it's a disaster.
Sorry, Mark if I trouble you. It's just out of curiousity, why C is better than Pascal. I still doing C in Metatrader, I like C, but I think Pascal is better than C.
Right, neither C nor C++ allows for functions to be nested inside other functions, although some current versions of C++ such as Visual Studio 2010 and later, allow the programmer to insert lambda expressions into a function or method. Lambda expressions are anonymous functions that are defined inline.Aside from Borland text editor which allow cursor to go up/down vertically
It's very convenient to access local variable globally.
Code:procedure Level1; var A: Integer; procedure Level2; procedure Level3; begin A:=10; { don't have to put A in global scope } end; begin end; begin end;
IMO, it's only mildly convenient to be able to index arrays starting at other than zero. Many languages have this capability, among them Basic and Fortran.Stephanus said:
If you write your own constructor in C++, rather than rely on a default constructor, you can have it do what you want.Stephanus said:
I'm starting to learn Python, myself. I'm finding it to be a very interesting language with lots of unusual capabilities.Stephanus said:But I know a kid, (not mine unfortunately
This is what we have to do in C. Move a to global.
int a; // accessed by level3
void level1()
{
int a;
a=50;
level3();
cout << a; / will output 50 instead of 20. C can't do that.
}
void level2()
{
}
void level3()
{
a=20;
}You don't have to do this, and it's usually not recommended. It's usually better to pass variables in the parameter list
void level1()
{
int a;
a=50;
level3(a);
cout << a; // will output 50 instead of 20. C can't do that.
}
void level3(int b)
{
// level3 has read access to level1's a.
printf("b is %d", b); // prints "b is 50"
}Wow, I'm still using Delphi 3, 1996 version. I have a qr barcode library, can't find for the newer version. So I am stuck with it. I just realized, it's been 19 years. The longest programming language that I code.