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digitalmars.D - Allow "deprecated" to accept more than string literals while parsing

reply "Brian Schott" <briancschott gmail.com> writes:
Here's something that I ran into while writing dfix`s implicit 
string concatenation cleanup code:

```
// accepted
deprecated("This function is dumb and you shouldn't use it)
void deleteT3hH4rdDisk();

// accepted
deprecated("This function is dumb and" " you shouldn't use it)
void deleteT3hH4rdDisk();

// parse error
deprecated("This function is dumb and" ~ " you shouldn't use it)
void deleteT3hH4rdDisk();
```

According to this[1] the behavior is correct, however it is not 
intuitive that a programmer cannot split up the string for 
"deprecated" over multiple lines without depending on D's 
bug-prone behavior of implicitly joining adjacent string literals.

There are two solutions to this that I see, one is to allow a 
combination of string literals and "~" operators, and the other 
is to allow arbitrary expressions that evaluate to a string.

Right now I favor allowing string literals and "~" because it's a 
smaller change. I can write up a DIP for this if there's a decent 
chance of this getting approved.

[1] http://dlang.org/grammar.html#DeprecatedAttribute
May 31 2015
next sibling parent reply Steven Schveighoffer <schveiguy yahoo.com> writes:
On 5/31/15 11:33 PM, Brian Schott wrote:

 Here's something that I ran into while writing dfix`s implicit string
 concatenation cleanup code:

 ```
 // accepted
 deprecated("This function is dumb and you shouldn't use it)
 void deleteT3hH4rdDisk();

 // accepted
 deprecated("This function is dumb and" " you shouldn't use it)
 void deleteT3hH4rdDisk();

 // parse error
 deprecated("This function is dumb and" ~ " you shouldn't use it)
 void deleteT3hH4rdDisk();
 ```


Am I missing something, or is the trailing quote not required? (missing 
in all 3 examples).

-Steve
Jun 01 2015
parent "Brian Schott" <briancschott gmail.com> writes:
On Monday, 1 June 2015 at 15:24:37 UTC, Steven Schveighoffer 
wrote:

 Am I missing something, or is the trailing quote not required? 
 (missing in all 3 examples).


Either that or I made a typo and copied/pasted it.
Jun 01 2015
prev sibling parent reply "Dicebot" <public dicebot.lv> writes:
Is there any reason to not allow argument to be any expression 
and reject non-string ones at semantic phase?
Jun 02 2015
next sibling parent "Jonathan M Davis" <jmdavisProg gmx.com> writes:
On Tuesday, 2 June 2015 at 18:44:30 UTC, Dicebot wrote:

 Is there any reason to not allow argument to be any expression 
 and reject non-string ones at semantic phase?


Probably just simplicity and the fact that it really doesn't make 
sense to use anything other than a string literal in a deprecated 
message. It's just that not allowing ~ in it makes it difficult 
when the string gets long (which you usually should avoid, but 
sometimes, it's unavoidable).

Personally, I don't really care with any string argument is 
permitted so long as its value is known at compile time, but the 
only way that it would even vaguely make sense was if someone 
were doing something to automatically generate deprecation 
messages, which seems rather odd to me. Maybe so they can put a 
date in them, and they only want to put that date in one place? 
Certainly, I have to stretch to think of a reason why you'd ever 
do anything more than "msg" or "msg" ~ "msg".

- Jonathan M Davis
Jun 02 2015
prev sibling parent "Daniel Murphy" <yebbliesnospam gmail.com> writes:
"Dicebot"  wrote in message news:odfsgqcftykjkztsgqmc forum.dlang.org...


 Is there any reason to not allow argument to be any expression and reject 
 non-string ones at semantic phase?


The original reason is that trying to reference manifest constants etc from 
that context resulted in forward reference errors, so allowing only string 
literals was easier.  I'm guessing those problems have since been fixed, so 
allowing any ct expression that resolves to a string should be fine now.
Jun 03 2015