Is there an opposite of .toString()?

[myst]

On Saturday, 14 October 2017 at 03:47:29 UTC, Jonathan M Davis 
wrote:
> The function to use for conversions in general is std.conv.to. 
> And really, there isn't much of a reason to ever call toString. 
> Functions like writeln, format, and to may use it internally, 
> but it's more or less an anti-pattern to do so in your own code 
> - especially if we're talking about generic code. If you're 
> looking to convert something to string, to!string works with 
> pretty much everything and toString works with considerably 
> less. And if there's a generic way to convert from string to 
> something else, it's also with to - e.g. to!int("42"). However, 
> for that conversion to work, it either has to be a built-in 
> type so that to understands it, or the type will need a 
> constructor that takes a string. In general, in order to 
> generically convert to a user-defined type, either that target 
> type must have a constructor that accepts that source type, or 
> the source type must define opCast or an alias to convert to 
> the target type. std.conv.to is very powerful, but it does need 
> to have something to work with. If anything approaching a 
> standard conversion exists, it can be done with std.conv.to; 
> otherwise, it's going to depend on the type.
>
> I think that in general, you're going to find that converting 
> to a string works with most everything, but aside from built-in 
> types, converting from a string with std.conv.to is unlikely to 
> work. _Some_ types do have constructors that take strings, but 
> most don't. Built-in types will work, because std.conv.to 
> understands how to do that conversion. For user-defined types, 
> either you're likely going to have to parse the string 
> yourself, or they may contain another function for doing the 
> conversion (for instance std.datetime.systime.SysTime uses 
> toISOExtString and fromISOExtString to convert to and from the 
> ISO extended format for a date and time and has other functions 
> for other time formats).

This is not what I asked about.

> You can also check out std.conv.parse, which acts similarly to 
> std.conv.to, but whereas to converts the entire string, parse 
> converts the first portion of a string and therefore is meant 
> to allow for parsing multiple values from a string.

This is what I asked about. Thanks.