Re: Warning for "confusable" types

On Fri, Oct 11, 2019, at 1:46 PM, Bishop Bettini wrote: > On Fri, Oct 11, 2019 at 1:47 PM Larry Garfield <larry@garfieldtech.com> > wrote: > > > On Fri, Oct 11, 2019, at 8:54 AM, Nikita Popov wrote: > > > Hi internals, > > > > > > Something I've seen play out a couple of times: Newbies try to use > > > something like "integer" or "resource" as a type, and then get a > > confusing > > > error message along the lines of "must be an instance of resource, > > resource > > > given". > > > > > > I would like to throw a compiler warning in this case, that looks as one > > of > > > the following: > > > > > > > Warning: "integer" will be interpreted as a class type. Did you mean > > > "int"? Use qualified name or "use" to suppress this warning > > > > > > > Warning: "resource" is not a supported builtin type and will be > > > interpreted as a class type. Use qualified name or "use" to suppress this > > > warning > > > > > > This warning only triggers if the type is lowercase (integer but not > > > Integer), is unqualified (integer but not \integer) and is not imported > > > (there is no "use integer"). This provides multiple ways to avoid the > > > warning for code that does legitimately want to use lowercase "integer" > > as > > > a class type. > > > > > > Implementation: https://github.com/php/php-src/pull/4815 > > > > > > > > > Thoughts? > > > > > > Nikita > > > > Can you clarify where exactly "compiler warning" would be displayed? Is > > that an E_WARNING? How would I as a user see a message when I write > > > > function foo(integer $a) { ... } > > > > It's an E_COMPILE_WARNING, and arises when the compiler sees you're type > hinting for a class, but no such class loaded. This checks that given class > against a known list of "probable mistakes" and provides guidance. Eg, I > typed "integer $a" when I mean "int $a", and don't understand the > current > compiler warning: "Argument 1 passed to foo must be an instance of integer, > int given" > > See also https://stackoverflow.com/a/40638544/2908724 OK, so it's just taking an existing error message and customizing it in cases where we have a good idea of what the user got wrong? That's a very +1 in my book. --Larry Garfield