On 16/06/2017 2:04 PM, Radford Neal wrote:
On Wed, 14 Jun 2017, G?bor Cs?rdi wrote:
I like the idea of string literals, but the C/C++ way clearly does not
work. The Python/Julia way might, i.e.:
"""this is a
multi-line
lineral"""
luke-tier...@uiowa.edu:
This does look like a promising option; some more careful checking
would be needed to make sure there aren't cases where currently
working code would be broken.
I don't see how this proposal solves any problem of interest.
String literals can already be as long as you like. The problem is
that they will get wrapped around in an editor (or not all be
visible), destroying the nice formatting of your program.
With the proposed extension, you can write long string literals with
short lines only if they were long only because they consisted of
multiple lines. Getting a string literal that's 79 characters long
with no newlines (a perfectly good error message, for example) to fit
in your 80-character-wide editing window would still be impossible.
Furthermore, these Python-style literals have to have their second
and later lines start at the left edge, destroying the indentation
of your program (supposing you actually wanted to use one).
In contrast, C-style concatenation (by the parser) of consecutive
string literals works just fine for what you'd want to do in a
program. The only thing they wouldn't do that the Python-style
literals would do is allow you to put big blocks of literal text in
your program, without having to put quotes around each line. But
shouldn't such text really be stored in a separate file that gets
read, rather than in the program source?
I agree with most of this, but I still don't see the need for a syntax
change. That's a lot of work just to avoid typing "paste0" and some
commas in
paste0("this is the first part",
"this is the second part")
If the rather insignificant amount of time it takes to execute this
function call really matters (and I'm not convinced of that), then
shouldn't it be solved by the compiler applying constant folding to
paste0()?
(Some syntax like r"xyz" to make it easier to type strings containing
backslashes and quotes would actually be useful, but that's a different
issue.)
Duncan Murdoch
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