What a L"string" in front of square brackets mean?

Question

I found this among a supposedly trivial Tetris console game code.

wchar_t *screen = new wchar_t[];
unsigned char *pField;
.
.
.
screen[someMathIndex] = L" ABCDEFG=#"[pField[someOtherMathIndex]];

What is an wchar string in front of square brackets even mean? I can't even able to find a way to google it. Can you redirect me to some resource of this strange thing maybe.

it's getting a wide char out of the string `L" ABCDEFG=#"` at the index `pField[someOtherMathIndex]` — Ruzihm, Mar 22 '21 at 20:57
The complete list of Microsoft C++ prefixes: https://learn.microsoft.com/en-us/cpp/cpp/string-and-character-literals-cpp — Simon Mourier, Mar 22 '21 at 21:02
Note that `new wchar_t[];` is not valid C++. You have to specify the size of the array being allocated, eg: `wchar_t *screen = new wchar_t[SomeSizeHere];` — Remy Lebeau, Mar 22 '21 at 21:07
Yes it is specified in the actual code...I omitted it actually. — MILO, Mar 22 '21 at 21:10
The same as `pField[someOtherMathIndex][L" ABCDEFG=#"]` of course. — Yakk - Adam Nevraumont, Mar 22 '21 at 22:11

NathanOliver · Accepted Answer · 2021-03-22T21:03:24.040

5

String literals in C++ are actually arrays. I this case L" ABCDEFG=#" is a const wchar_t[11]. When you do

L" ABCDEFG=#"[pField[someOtherMathIndex]]

You are going to the pField[someOtherMathIndex]'th index of that wchar_t array.

edited Mar 22 '21 at 21:03

answered Mar 22 '21 at 20:57

NathanOliver

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Never seen this. Thank you very much. – MILO Mar 22 '21 at 21:06
@MILO No problem. I've never seen someone do this either. Typically that string literal would be in a named variable like `wchar_t CoolString[] = L" ABCDEFG=#";` and then you would just have in the code `CoolString[pField[someOtherMathIndex]]` – NathanOliver Mar 22 '21 at 21:07

What a L"string" in front of square brackets mean?

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