Translate into if?

Projects Programming
1

How would i make this into an if statement?

digitalWrite(lager_pins[!L 2 ? : L - 2], HIGH);

With the ! And ?.. i can’t understand it.

2

That looks like a ternary expression except that the syntax is wrong.

The ! is logical not.

3

Invalid syntax:

error: expected ']' before numeric constant
   digitalWrite(lager_pins[!L 2 ? : L - 2], HIGH); 
                              ^

Perhaps you meant:

  digitalWrite(lager_pins[!L ? 2 : L - 2], HIGH);

That would be equivalent to:

if (!L)
  digitalWrite(lager_pins[2], HIGH);
else
 digitalWrite(lager_pins[L - 2], HIGH);

Which in turn would be equivalent to:

if (L == 0)
  digitalWrite(lager_pins[2], HIGH);
else
 digitalWrite(lager_pins[L - 2], HIGH);
4

johnwasser:
Invalid syntax:

error: expected ']' before numeric constant

digitalWrite(lager_pins[!L 2 ? : L - 2], HIGH);
                              ^





Perhaps you meant:

digitalWrite(lager_pins[!L ? 2 : L - 2], HIGH);




That would be equivalent to:

if (!L)
  digitalWrite(lager_pins[2], HIGH);
else
digitalWrite(lager_pins[L - 2], HIGH);




Which in turn would be equivalent to:

if (L == 0)
  digitalWrite(lager_pins[2], HIGH);
else
digitalWrite(lager_pins[L - 2], HIGH);

In which case, what happens when L == 1?

5 
if (L == 0)
  digitalWrite(lager_pins[2], HIGH);
else
 digitalWrite(lager_pins[L - 2], HIGH);

In which case, what happens when L == 1?

Since 1 is not equal to 0 the else executes,

6

darrob:
In which case, what happens when L == 1?

Objection! Assumes facts not in evidence.
Let's hope that whatever code this is part of doesn't execute this line with L=1.

7

Sustained. Oops. == != =.

8

johnwasser:
Let's hope that whatever code this is part of doesn't execute this line with L=1.

Why not?
We don't know enough about the OP's code (hint) to form an opinion