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MilchoPenchev

Eight, Nine, Ten...

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Could be binary coded decimal... and it makes outputting a text value easier as well ;)

 

Manic Miner on the ZX Spectrum didn't even store the game score or high score in a variable... it just used ASCII text on the screen (the screen area where the score was displayed was never cleared).

 

The algorithm only added to your score either 1 or 10 or 100 at a time IIRC. It just increased the ASCII value at the screen position by 1 and if that makes it > 9 it made the current digit 0 and added 1 to the next digit along (and looped if that was bumped to > 9 as well).

 

It then just copied the score to the high score location if the score was larger than the current high score (check was done with another ASCII comparison).

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MilchoPenchev    1178

Could be binary coded decimal... [snip]

 

That sounds so convoluted it requires its own thread. 

Unfortunately that wasn't the case here - this code, according to a colleague who originally fixed it - caused a fatal crash in the software. 

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cr88192    1570

Obvious, the coder has 8 fingers on each hand

... maybe the use of named constants is what was at fault here ...

...
#define FOURTY_TWO (042)
#define NINETEEN_EIGHTY_FOUR (NINETEEN, EIGHTY, FOUR)
...

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Bacterius    13165

That's even worse!!!

This used to happen to me when I was trying to align constants properly. Nowadays I just put spaces instead, been burned too often by this damn octal notation "feature" which I'm guessing nobody actually uses, except the odd raw socket hacker (if even). Permission bits are another one, but constants for those are already defined anyway.

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cr88192    1570


That's even worse!!!

This used to happen to me when I was trying to align constants properly. Nowadays I just put spaces instead, been burned too often by this damn octal notation "feature" which I'm guessing nobody actually uses, except the odd raw socket hacker (if even). Permission bits are another one, but constants for those are already defined anyway.


at one point I made things more orthogonal (for my script language) by adding several number notations:
0b... //binary
0c... //octal
0d... //decimal
in addition to:
0x... //hexadecimal

then got into a big mental debate as to whether or not to keep '0' by itself as an octal prefix, make it decimal, or maybe just deprecate it and issue a warning...

note, '_' is also a spacer, so:
0d999_999_999
is the same as:
999999999

likewise:
0x5CD13A42_3B9AC9FFL
or:
999_999_999_999_999_999L
or:
0x0DE0_B6B3__A763_FFFFL

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Octal was big back in the day when C was being made, maybe even moreso than hexadecimal. These days nobody really uses it since it can't be aligned nicely to 8-bit (some computers back then had words with a bit count multiple of 3, so octal probably made a lot more of sense).

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Cornstalks    7030

But they could have made it useful by adding pluses!

#define ONE     +1
#define TWENTY  +20
#define HUNDRED +100
 
// Here's a little example
#include <iostream>
 
int main()
{
    int x = ONE;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED TWENTY;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED TWENTY ONE;
    std::cout << x << std::endl;
}

 

Or even worse:

 
#define ONE     +0x001
#define TWENTY  +0x020
#define HUNDRED +0x100
Edited by Cornstalks

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Trienco    2555

Still trying to figure out the reasoning behind that. Is that what happens when your code analysis tool complains about "magic numbers" and somebody just decides to "fix it"?

 

Because having one such tool complain about '0' being a "magic number" really made me question the worth of that tool and what the creators' code would look like.

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Bacterius    13165

But they could have made it useful by adding pluses!

#define ONE     +1
#define TWENTY  +20
#define HUNDRED +100
 
// Here's a little example
#include <iostream>
 
int main()
{
    int x = ONE;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED TWENTY;
    std::cout << x << std::endl;
 
    x = ONE HUNDRED TWENTY ONE;
    std::cout << x << std::endl;
}

 

Or even worse:

 
#define ONE     +0x001
#define TWENTY  +0x020
#define HUNDRED +0x100

 

Sadly this doesn't fully work: 

 

 

TWO HUNDRED == 102

But don't worry - we can fix it! We just need to be "clever"...

 

 

#define AND +0
#define ONE +1
#define TWO +2
#define TWENTY +20
#define HUNDRED *100
 
// Here's a little example
#include <iostream>
 
int main()
{
    int x = TWO HUNDRED AND TWENTY ONE;
    std::cout << x << std::endl;
    // prints 221
}

 

This way you even get to write grammatically correct numbers. happy.png

Edited by Bacterius

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Cornstalks    7030

*snip*

Ah, good catch!
 

I think we should pool our efforts and make a programming language where this kind of thing is sane.

I was hoping for a more concise solution, but here we go (so now you can use commas and hyphens in your numbers!):
#include <type_traits>

template <typename T>
struct Number
{
    mutable T n;
    Number(T n) : n(n) {}

    const Number<T> operator+() const
    {
        return *this;
    }

    template <typename U>
    const Number<typename std::common_type<T, U>::type> operator, (const Number<U>& num) const
    {
        return n + num.n;
    }

    template <typename U>
    const Number<typename std::common_type<T, U>::type> operator- (const Number<U>& num) const
    {
        return n + num.n;
    }

    template <typename U>
    const Number<typename std::common_type<T, U>::type> operator+ (const Number<U>& num) const
    {
        return n + num.n;
    }

    template <typename U>
    const Number<typename std::common_type<T, U>::type> operator* (const Number<U>& num) const
    {
        return n * num.n;
    }

    operator T() const
    {
        return n;
    }
};

Number<unsigned long long> operator"" _n(unsigned long long n)
{
    return n;
}

#define ONE      +1_n
#define TWO      +2_n
#define THREE    +3_n
#define FOUR     +4_n
// ... add more if you wish
#define TWENTY   +20_n
#define HUNDRED  *100_n
#define THOUSAND *1000_n
#define AND

#define TIMES *
#define MINUS -

#include <iostream>

int main()
{
    // The only real drawback is that you have to surround them with parentheses if you use ,
    int x = (FOUR THOUSAND, ONE HUNDRED AND TWENTY-THREE);
    int y = (ONE HUNDRED AND ONE);
    int result = x TIMES y;
    std::cout << x << " * " << y << " = " << result << std::endl;

    result = x MINUS y;
    std::cout << x << " - " << y << " = " << result << std::endl;
}
Edited by Cornstalks

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blutzeit    1650

Good thing they put parentheses around those literals!

 

edit:

Oh gosh, I didn't even realize the TEN issue... That's horrible.

 

 

I don't understand, the only problem is that it's not complete? Here's an excerpt from the full definition:

 
#define EIGHT  (0x08) 
#define NINE   (0x09)
#define AYE    (0x0A)
#define BEE    (0x0B)
#define CEE    (0x0C)
#define DEE    (0x0D)
#define EE     (0x0E)
#define EFF    (0x0F)
#define TEN    (0x10)
...
#define NINETEEN (0x19)
#define AYETEEN  (0x1A)
#define BEETEEN  (0x1B)
...
#define NINETYEFF (0x9F)
...
#define AYETYDEE  (0xAD)
...
#define EFFTYEFF  (0xFF)

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