D - Python inspirations
- Matthew Wilson (13/13) Apr 10 2003 Being doing Python of late, and am impressed with some of the nice featu...
- J C Calvarese (6/26) Apr 10 2003 You've got my interest. That sounds useful. Should we consider
- Matthew Wilson (17/43) Apr 10 2003 For me I don't see the need for a new keyword, partly because I'm aware ...
- Dan Liebgold (32/38) Apr 10 2003 No! This type of syntax is misleading, especially in the case of the wh...
- Luna Kid (6/19) Apr 10 2003 I've seen this mentioned somewhere in this NG.
- DDevil (20/35) Apr 10 2003 Why not use the exception mechanism?
- Matthew Wilson (3/38) Apr 10 2003 Notwithstanding other objections, there's the issue of performance.
- DDevil (19/20) Apr 10 2003 Well then there's always goto (braces added for clarity).
- Patrick Down (3/5) Apr 10 2003 I'm all for it. I've made the same sugestion here before.
- Stephen Waits (4/7) Apr 12 2003 Matt,
- Walter (14/27) May 23 2003 features.
- Matthew Wilson (5/36) May 27 2003 What if there are multiple breaks?
- Walter (5/46) Jun 06 2003 You can use:
Being doing Python of late, and am impressed with some of the nice features.
One in particular I've always thought would be nice to have in C or C++ is
for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Any takers for D?
Apr 10 2003
You've got my interest. That sounds useful. Should we consider
calling it something new like "forelse" for example? How costly is
having a new keyword when it's much easiler for the uninitiated to guess
what's going on?
Justin
Matthew Wilson wrote:
Being doing Python of late, and am impressed with some of the nice features.
One in particular I've always thought would be nice to have in C or C++ is
for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Any takers for D?
Apr 10 2003
For me I don't see the need for a new keyword, partly because I'm aware how
phobic language designers hate adding reserved words. But also, it seems
that else-ing constructs is something that we may want to extend, so else
becomes something of a general concept (which it is anyway, I guess).
For example, there's no reason why we wouldn't also use it for `while` as
well as `for` as in
while(!b)
{
}
else
{
// This is called if the while was broken
}
"J C Calvarese" <jcc-47 excite.com> wrote in message
news:b74qdr$3rd$1 digitaldaemon.com...
You've got my interest. That sounds useful. Should we consider
calling it something new like "forelse" for example? How costly is
having a new keyword when it's much easiler for the uninitiated to guess
what's going on?
Justin
Matthew Wilson wrote:
Being doing Python of late, and am impressed with some of the nice
features.
One in particular I've always thought would be nice to have in C or C++
is
for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Any takers for D?
Apr 10 2003
Dan Liebgold <Dan_member pathlink.com>
No! This type of syntax is misleading, especially in the case of the while
loop. It seems like the else would be executed when the condition were *never*
true. For example:
if (test) {
}
else {
// executed when test false
}
versus...
while (test) {
}
else {
// not necessarily executed when test false, instead connected with a break
statement (!!?)
}
The for loop version isn't much better... I think this can already be done if
function literal expressions were extended slightly to allow an immediate call,
for example:
thing find_thing (char[] thing_name) {
if (delegate thing(name) { for (int i =0; i < COUNT; ++i) { /* look for name */
return found_thing; }(thing_name)) {
// executed if found
}
else {
// executed if not found
}
}
It looks odd, but it really isn't! ;) The scoping doesn't change, and you
can pass back any type you like (so you could embed such an immediate literal
call in a switch for example). The trick is to format the code better....
Dan
In article <b74red$4c8$1 digitaldaemon.com>, Matthew Wilson says...
For me I don't see the need for a new keyword, partly because I'm aware how
phobic language designers hate adding reserved words. But also, it seems
that else-ing constructs is something that we may want to extend, so else
becomes something of a general concept (which it is anyway, I guess).
For example, there's no reason why we wouldn't also use it for `while` as
well as `for` as in
Apr 10 2003
I've seen this mentioned somewhere in this NG. And I sort of like it, too. Luna Kid "Matthew Wilson" <dmd synesis.com.au> wrote in message news:b74p8g$35v$2 digitaldaemon.com...Being doing Python of late, and am impressed with some of the nicefeatures.One in particular I've always thought would be nice to have in C or C++ is for-else, as in for(int i = 0; i < 10; ++i) { // do some stuff } else { /// This only called if the for loop is terminated with a break statement. } Any takers for D?
Apr 10 2003
Why not use the exception mechanism?
try
{
for (int i = 0; i < 10; i++)
{
// Do stuff
...
if (something)
throw(Error); // Instead of break
}
}
catch (Error)
{
// Do stuff here if exception (break)
}
Of course that doesn't look quite as minimalistic, but the behavior is
possibly more explicit and clear.
--
// DDevil
On Fri, 11 Apr 2003 07:56:02 +1000, Matthew Wilson wrote:
Being doing Python of late, and am impressed with some of the nice
features.
One in particular I've always thought would be nice to have in C or C++
is for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Apr 10 2003
Notwithstanding other objections, there's the issue of performance.
"DDevil" <ddevil functionalfuture.com> wrote in message
news:pan.2003.04.11.00.35.05.574731 functionalfuture.com...
Why not use the exception mechanism?
try
{
for (int i = 0; i < 10; i++)
{
// Do stuff
...
if (something)
throw(Error); // Instead of break
}
}
catch (Error)
{
// Do stuff here if exception (break)
}
Of course that doesn't look quite as minimalistic, but the behavior is
possibly more explicit and clear.
--
// DDevil
On Fri, 11 Apr 2003 07:56:02 +1000, Matthew Wilson wrote:
Being doing Python of late, and am impressed with some of the nice
features.
One in particular I've always thought would be nice to have in C or C++
is for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Apr 10 2003
Well then there's always goto (braces added for clarity).
for (int i = 0; i < 10; i++)
{
// Do stuff
...
if (something)
goto Error; // Instead of break
}
goto Done;
{
Error:
// Do stuff here for the break condition
}
Done:
// Code continues
It's fast anyway. ;-)
--
// DDevil
On Fri, 11 Apr 2003 11:28:55 +1000, Matthew Wilson wrote:
Notwithstanding other objections, there's the issue of performance.
Apr 10 2003
"Matthew Wilson" <dmd synesis.com.au> wrote in news:b74p8g$35v$2 digitaldaemon.com:One in particular I've always thought would be nice to have in C or C++ is for-else, as inI'm all for it. I've made the same sugestion here before.
Apr 10 2003
Matthew Wilson wrote:One in particular I've always thought would be nice to have in C or C++ is for-else, as inMatt, Sadly I have to say this is insanely ugly. --Steve
Apr 12 2003
"Matthew Wilson" <dmd synesis.com.au> wrote in message news:b74p8g$35v$2 digitaldaemon.com...Being doing Python of late, and am impressed with some of the nicefeatures.One in particular I've always thought would be nice to have in C or C++ is for-else, as in for(int i = 0; i < 10; ++i) { // do some stuff } else { /// This only called if the for loop is terminated with a break statement. } Any takers for D?How about: for (int i = 0; i < 10; ++i) { // do some stuff if (condition) { // This only executed if the for loop is terminated with a break statement break; } }
May 23 2003
What if there are multiple breaks? (I know, I know: local functions) "Walter" <walter digitalmars.com> wrote in message news:bampoi$10mn$2 digitaldaemon.com..."Matthew Wilson" <dmd synesis.com.au> wrote in message news:b74p8g$35v$2 digitaldaemon.com...isBeing doing Python of late, and am impressed with some of the nicefeatures.One in particular I've always thought would be nice to have in C or C++for-else, as in for(int i = 0; i < 10; ++i) { // do some stuff } else { /// This only called if the for loop is terminated with a break statement. } Any takers for D?How about: for (int i = 0; i < 10; ++i) { // do some stuff if (condition) { // This only executed if the for loop is terminated with a break statement break; } }
May 27 2003
You can use:
break label;
"Matthew Wilson" <matthew stlsoft.org> wrote in message
news:bb1gip$2j6s$1 digitaldaemon.com...
What if there are multiple breaks?
(I know, I know: local functions)
"Walter" <walter digitalmars.com> wrote in message
news:bampoi$10mn$2 digitaldaemon.com...
"Matthew Wilson" <dmd synesis.com.au> wrote in message
news:b74p8g$35v$2 digitaldaemon.com...
Being doing Python of late, and am impressed with some of the nice
features.
One in particular I've always thought would be nice to have in C or
C++
is
for-else, as in
for(int i = 0; i < 10; ++i)
{
// do some stuff
}
else
{
/// This only called if the for loop is terminated with a break
statement.
}
Any takers for D?
How about:
for (int i = 0; i < 10; ++i)
{
// do some stuff
if (condition)
{
// This only executed if the for loop is terminated with a break
statement
break;
}
}
Jun 06 2003