How to split a string literal across multiple lines in C / Objective-C?

Question

I have a pretty long sqlite query:

const char *sql_query = "SELECT statuses.word_id FROM lang1_words, statuses WHERE statuses.word_id = lang1_words.word_id ORDER BY lang1_words.word ASC";

How can I break it in a number of lines to make it easier to read? If I do the following:

const char *sql_query = "SELECT word_id
                        FROM table1, table2
                        WHERE table2.word_id = table1.word_id
                        ORDER BY table1.word ASC";

I am getting a error.

Is there a way to write queries in multiple lines?

Answer 1

There are two ways to split strings over multiple lines:

Using \

All lines in C can be split into multiple lines using \.

Plain C:

char *my_string = "Line 1 \
                   Line 2";

Objective-C:

NSString *my_string = @"Line1 \
                        Line2";

Better approach

There's a better approach that works just for strings.

Plain C:

char *my_string = "Line 1 "
                  "Line 2";

Objective-C:

NSString *my_string = @"Line1 "
                       "Line2";    // the second @ is optional

The second approach is better, because there isn't a lot of whitespace included. For a SQL query however, both are possible.

Answer 2

You can also do:

NSString * query = @"SELECT * FROM foo "
                   @"WHERE "
                     @"bar = 42 "
                     @"AND baz = datetime() "
                   @"ORDER BY fizbit ASC";

Answer 3

You could also go into XCode -> Preferences, select the Indentation tab, and turn on Line Wrapping.

That way, you won't have to type anything extra, and it will work for the stuff you already wrote. :-)

One annoying thing though is...

if (you're long on indentation
    && short on windows) {
            then your code will
                end up squished
                     against th
                         e side
                             li
                              k
                              e

                              t
                              h
                              i
                              s
}