Calling `try` with a non-error-union argument, could suggest dropping the `try` call

[mark-rushakoff]

Zig Version

0.14.0-dev.2050+4adf63aef

Steps to Reproduce and Observed Output

I mistakenly thought that ArrayList.init could fail to allocate, so I prefixed it with try:

// a.zig

const std = @import("std");

pub fn main() void {
    const list = try std.ArrayList(u8).init(std.heap.page_allocator);
    std.debug.print(list.capacity);
}

This resulted in this error:

/tmp/a.zig:6:44: error: expected error union type, found 'array_list.ArrayListAligned(u8,null)'
    const list = try std.ArrayList(u8).init(std.heap.page_allocator);
                     ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

I am still learning Zig, so it took me a minute to interpret the error message and understand that try was what was wrong/unnecessary on that source line.

Expected Output

The inverse of this mistake -- a call that returns an error union which is unhandled -- offers a note suggesting how to address the compile error:

/tmp/b.zig:7:16: error: error union is ignored
    list.insert(0, 0);
    ~~~~~~~~~~~^~~~~~
/tmp/b.zig:7:16: note: consider using 'try', 'catch', or 'if'

The original mistake I made of using try when it is unnecessary, could output a suggestion to drop the try:

/tmp/a.zig:6:44: error: expected error union type, found 'array_list.ArrayListAligned(u8,null)'
    const list = try std.ArrayList(u8).init(std.heap.page_allocator);
                     ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/a.zig:6:44: note: consider omitting 'try'

The note is obviously much easier for a human to parse, and it would be particularly helpful to new Zig users.

I looked through Sema.zig but did not see any existing calls to sema.errNote that suggest removing a call, so I am not sure if there is precedence on exact phrasing for this case.