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Failure to compile raw string literals for ascii art

Sep 14, 2020 at 4:51pm
levilone (28)
So I'm trying to use ascii art in a game I'm writing for terminal, and the slashes cause errors because they are escape sequences. Supposedly using raw string literals should fix this problem. But my compiler (g++ on ubuntu 20.04) doesn't seem to recognize the R before my string, so I'm confused. The errors still show the escape sequences, but now also show "stray R in program".

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#include <iostream>
#include <string>
using namespace std;

int main()
{
	string str1 = R" __      __.__                         .___  __      __            .__       .";
	string str2 = R"/  \    /  \__|____________ _______  __| _/ /  \    /  \___________|  |    __| _/"; 
	string str3 = R"\   \/\/   /  \___   /\__  \\_  __ \/ __ |  \   \/\/   /  _ \_  __ \  |   / __ |"; 
	string str4 = R" \        /|  |/    /  / __ \|  | \/ /_/ |   \        (  <_> )  | \/  |__/ /_/ |"; 
	string str5 = R"  \__/\  / |__/_____ \(____  /__|  \____ |    \__/\  / \____/|__|  |____/\____ |"; 
	string str6 = R"   \/  \/           \/     \/           \/         \/                         \/"; 
	
	return 0;
}
Edit & run on cpp.sh

My terminal output is:
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ame2.cpp:7:19: error: invalid character ' ' in raw string delimiter
    7 |  string str1 = R" __      __.__                         .___  __      __            .__       .";
      |                ^   
game2.cpp:7:16: error: stray ‘R’ in program
game2.cpp:8:20: error: invalid character ' ' in raw string delimiter
    8 |  string str2 = R"/  \    /  \__|____________ _______  __| _/ /  \    /  \___________|  |    __| _/";
      |                ^    
game2.cpp:8:16: error: stray ‘R’ in program
game2.cpp:9:19: error: invalid character '\' in raw string delimiter
    9 |  string str3 = R"\   \/\/   /  \___   /\__  \\_  __ \/ __ |  \   \/\/   /  _ \_  __ \  |   / __ |";
      |                ^   
game2.cpp:9:16: error: stray ‘R’ in program
game2.cpp:10:19: error: invalid character ' ' in raw string delimiter
   10 |  string str4 = R" \        /|  |/    /  / __ \|  | \/ /_/ |   \        (  <_> )  | \/  |__/ /_/ |";
      |                ^   
game2.cpp:10:16: error: stray ‘R’ in program
game2.cpp:11:19: error: invalid character ' ' in raw string delimiter
   11 |  string str5 = R"  \__/\  / |__/_____ \(____  /__|  \____ |    \__/\  / \____/|__|  |____/\____ |";
      |                ^   
game2.cpp:11:16: error: stray ‘R’ in program
game2.cpp:12:19: error: invalid character ' ' in raw string delimiter
   12 |  string str6 = R"   \/  \/           \/     \/           \/         \/                         \/";
      |                ^   
game2.cpp:12:16: error: stray ‘R’ in program
game2.cpp: In function ‘int main()’:
game2.cpp:8:17: warning: unknown escape sequence: '\040'
    8 |  string str2 = R"/  \    /  \__|____________ _______  __| _/ /  \    /  \___________|  |    __| _/";
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
game2.cpp:8:17: warning: unknown escape sequence: '\_'
game2.cpp:8:17: warning: unknown escape sequence: '\040'
game2.cpp:8:17: warning: unknown escape sequence: '\_'
game2.cpp:9:17: warning: unknown escape sequence: '\040'
    9 |  string str3 = R"\   \/\/   /  \___   /\__  \\_  __ \/ __ |  \   \/\/   /  _ \_  __ \  |   / __ |";
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
game2.cpp:9:17: warning: unknown escape sequence: '\/'
game2.cpp:9:17: warning: unknown escape sequence: '\/'
game2.cpp:9:17: warning: unknown escape sequence: '\_'
game2.cpp:9:17: warning: unknown escape sequence: '\_'
game2.cpp:9:17: warning: unknown escape sequence: '\/'
game2.cpp:9:17: warning: unknown escape sequence: '\040'
game2.cpp:9:17: warning: unknown escape sequence: '\/'
game2.cpp:9:17: warning: unknown escape sequence: '\/'
game2.cpp:9:17: warning: unknown escape sequence: '\_'
game2.cpp:9:17: warning: unknown escape sequence: '\040'
game2.cpp:10:17: warning: unknown escape sequence: '\040'
   10 |  string str4 = R" \        /|  |/    /  / __ \|  | \/ /_/ |   \        (  <_> )  | \/  |__/ /_/ |";
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
game2.cpp:10:17: warning: unknown escape sequence: '\|'
game2.cpp:10:17: warning: unknown escape sequence: '\/'
game2.cpp:10:17: warning: unknown escape sequence: '\040'
game2.cpp:10:17: warning: unknown escape sequence: '\/'
game2.cpp:11:17: warning: unknown escape sequence: '\_'
   11 |  string str5 = R"  \__/\  / |__/_____ \(____  /__|  \____ |    \__/\  / \____/|__|  |____/\____ |";
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
game2.cpp:11:17: warning: unknown escape sequence: '\040'
game2.cpp:11:17: warning: unknown escape sequence: '\_'
game2.cpp:11:17: warning: unknown escape sequence: '\_'
game2.cpp:11:17: warning: unknown escape sequence: '\040'
game2.cpp:11:17: warning: unknown escape sequence: '\_'
game2.cpp:11:17: warning: unknown escape sequence: '\_'
game2.cpp:12:17: warning: unknown escape sequence: '\/'
   12 |  string str6 = R"   \/  \/           \/     \/           \/         \/                         \/";
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
game2.cpp:12:17: warning: unknown escape sequence: '\/'
game2.cpp:12:17: warning: unknown escape sequence: '\/'
game2.cpp:12:17: warning: unknown escape sequence: '\/'
game2.cpp:12:17: warning: unknown escape sequence: '\/'
game2.cpp:12:17: warning: unknown escape sequence: '\/'
game2.cpp:12:17: warning: unknown escape sequence: '\/'

Clearly I need to do some work to print out the ascii art.
Sep 14, 2020 at 4:56pm
ne555 (10692)
when in doubt, rtfm
https://en.cppreference.com/w/cpp/language/string_literal (6)
R"delimiter(raw_characters)delimiter"
so you need to write string str5 = R"( \__/\ / |__/_____ \(____ /__| \____ | \__/\ / \____/|__| |____/\____ |)";
(surround with parenthesis)
Last edited on Sep 14, 2020 at 4:58pm
Sep 14, 2020 at 5:03pm
levilone (28)
Oh, thank you, I kept reading that and I kept missing the parentheses, it compiled perfectly
Sep 14, 2020 at 5:04pm
seeplus (6623)
To use raw strings, you need to enclose the string in (). So eg:

 
 
std::string str1 = R"(this is a raw string \ containing a back slash)";

Sep 14, 2020 at 5:09pm
levilone (28)
I've got it done now and the final code looks like this:
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#include <iostream>
#include <string>
using namespace std;

int main()
{
	string str1 = R"( __      __.__                         .___  __      __            .__       .)";
	string str2 = R"(/  \    /  \__|____________ _______  __| _/ /  \    /  \___________|  |    __| _/)"; 
	string str3 = R"(\   \/\/   /  \___   /\__  \\_  __ \/ __ |  \   \/\/   /  _ \_  __ \  |   / __ |)"; 
	string str4 = R"( \        /|  |/    /  / __ \|  | \/ /_/ |   \        (  <_> )  | \/  |__/ /_/ |)"; 
	string str5 = R"(  \__/\  / |__/_____ \(____  /__|  \____ |    \__/\  / \____/|__|  |____/\____ |))"; 
	string str6 = R"(   \/  \/           \/     \/           \/         \/                         \/)";
	
	cout << str1 << endl;
	cout << str2 << endl;
	cout << str3 << endl;
	cout << str4 << endl;
	cout << str5 << endl;
	cout << str6 << endl;
	
	return 0;
}
Edit & run on cpp.sh

Which outputs this to the terminal:
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 __      __.__                         .___  __      __            .__       .
/  \    /  \__|____________ _______  __| _/ /  \    /  \___________|  |    __| _/
\   \/\/   /  \___   /\__  \\_  __ \/ __ |  \   \/\/   /  _ \_  __ \  |   / __ |
 \        /|  |/    /  / __ \|  | \/ /_/ |   \        (  <_> )  | \/  |__/ /_/ |
  \__/\  / |__/_____ \(____  /__|  \____ |    \__/\  / \____/|__|  |____/\____ |)
   \/  \/           \/     \/           \/         \/                         \/
Sep 14, 2020 at 7:23pm
jonnin (11491)
sweet, your mud is nearly ready :P
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