Mystery Code

Projects Programming
1

Hi,

RE: Convert string to long integer on Arduino - #5 by system - Libraries - Arduino Forum

Can somebody kindly explain to me these 2 lines of code from th eposted code above that look simple but have a strange arrangement.

First time I come across this kind of condition settings :

if (inString [inCount] == EndMarker) break;
{
(++inCount < INLENGTH);
inString[inCount] = 0; // null terminate the string
}

Q1: what is the { doing after the "if (inString [inCount] == EndMarker) break;" since the if condition is completed in a single line with a "break;"
is it similar to an "else{".

Q2: what is the equivalent of: (++inCount < INLENGTH); in lame man's code?

Thanks

2

Q1: what is the { doing after the "if (inString [inCount] == EndMarker) break;" since the if condition is completed in a single line with a "break;"
is it similar to an "else{".

C and C++ allow you to define blocks of code anywhere. Doing so does not have to make sense. In the snippet you posted, the curly braces define a useless block of code.

Q2: what is the equivalent of: (++inCount < INLENGTH); in lame man's code?

Equivalent in what sense?

    42;

is equivalent in that it accomplishes nothing.

3

PaulS:
C and C++ allow you to define blocks of code anywhere. Doing so does not have to make sense. In the snippet you posted, the curly braces define a useless block of code.
Equivalent in what sense?

    42;

is equivalent in that it accomplishes nothing.

Nothing, apart from incrementing "inCount"

4

PaulS:
C and C++ allow you to define blocks of code anywhere. Doing so does not have to make sense. In the snippet you posted, the curly braces define a useless block of code.
Equivalent in what sense?

    42;

is equivalent in that it accomplishes nothing.

Perhaps you meant to say "uselessly defines a block of code", as the code in the {} is not useless but blocking it is superfluous.

There are reasons to place curly braces around code other than to block for if/esle/for statements, you can worry about that later. Here it is harmless.

An "else" before that {block} in the OP's code would not change the interpretation and would make it a bit clearer maybe.

Calling

(++inCount < INLENGTH);

equivalent to

42;

we'll just have to chalk up to the breakfast effect - posting before proper nutrients have been delivered to the brain.

In "lame man's code", the line in question boils down to

++inCount;

It increments inCount. If we assume inCount is an integer, that means it adds one.

5

It looks like there used to be an if statement:

          if (++inCount < INLENGTH)
            inString[inCount] = 0;  // null terminate the string
6

Duplicate of Can someone please simplify the following 2 lines of code. - Programming Questions - Arduino Forum