Add ValueOr

What's Changed

• add ValueOr by @ItsMalma in #81

New Contributors

• @ItsMalma made their first contribution in #81

Full Changelog: v5.0.0...v6.0.0

Generics & more

• Now a Go module under the path github.com/guregu/null/v5
  • ⚠️ Please use this instead of from the former gopkg.in path.
  • Previously this package didn't use modules to support ancient pre-go mod environments, but now module support is required.
• Added missing types from database/sql: Int32, Int16, Byte
• Added generic Value[T] embedding sql.Null[T]
  • Note that zero.Value[T] requires that T is comparable. null.Value[T] supports any value.
  • This doesn't support TextMarshaler because there's no generic way to support all types (e.g. structs). We could support some types but I'm not sure if that's useful.
  • This type requires Go version ≥1.22, on lower versions it won't be present

Behavior from v4 is unchanged, so it should be an easy upgrade.
Thank you and enjoy.

What's Changed

• v5: More types, generics by @guregu in #77

Full Changelog: v4.0.0...v5.0.0

Major brush-up

This is a new major release that improves performance and fixes an inconsistency that existed in v3.

• null.Time and zero.Time now embed sql.NullTime.
• null.Time and zero.Time's UnmarshalText returns a blank string if invalid, making them consistent with the rest of the package (see #47).
• Errors returned by this package are now wrapped using Go 1.13-style errors.
• Support for unmarshaling from the JSON representation of sql.NullXXX objects (ex. {"Int64": 123, "Valid": true}) has been dropped, significantly improving unmarshaling time and reducing allocations.
• Unmarshaling errors no longer affect Valid. Always check for errors.

Support for Equal was added in the previous release.

Equal method

This release adds an Equal method to all types, for easy equality checks.
It also adds ValueOrZero to the zero package.
Types in the null package are considered Equal if they're either both invalid, or both valid and have the same value.
Types on the zero package are considered Equal if their ValueOrZero is the same, so an invalid string and a valid "" are equal.

This will be the last release before v4.

Time.IsZero

Adds IsZero methods for Time in line with the rest of the types.

ValueOrZero

Added a new method ValueOrZero to every type in the null package. This method returns the inner value if valid, or the zero value if invalid (similar to the zero package). See #17.

Return error when JSON-marshaling NaN or Infinity floats

If you try to JSON marshal Infinity or NaN, you'll get *encoding/json.UnsupportedValueError. This brings us in line with the standard library.

More flexible JSON parsing

Int and Float can now be read from JSON strings. #23

MarshalText for null.String

MarshalText was missing from null.String, but no longer!

Minor documentation fixes

This version updates the GoDoc to be consistent with the changes described in #10 and #14.