pub trait FromValue: Sized {
type Intermediate: TryFrom<Value, Error = FromValueError> + Into<Self>;
// Provided methods
fn from_value(v: Value) -> Self { ... }
fn from_value_opt(v: Value) -> Result<Self, FromValueError> { ... }
fn get_intermediate(v: Value) -> Result<Self::Intermediate, FromValueError> { ... }
}Expand description
Implement this trait to convert a value to some type.
The FromRow trait requires an ability to rollback this conversion to an original Value
instance. Thats the reason why there is the Intermediate type – consider implementing
Into<Value> for your Intermediate type if you want FromRow to work with your type.
Required Associated Types§
type Intermediate: TryFrom<Value, Error = FromValueError> + Into<Self>
Provided Methods§
sourcefn from_value(v: Value) -> Self
fn from_value(v: Value) -> Self
Will panic if could not convert v to Self.
sourcefn from_value_opt(v: Value) -> Result<Self, FromValueError>
fn from_value_opt(v: Value) -> Result<Self, FromValueError>
Will return Err(Error::FromValueError(v)) if could not convert v to Self.
sourcefn get_intermediate(v: Value) -> Result<Self::Intermediate, FromValueError>
fn get_intermediate(v: Value) -> Result<Self::Intermediate, FromValueError>
Will return Err(Error::FromValueError(v)) if v is not convertible to Self.
Implementations on Foreign Types§
source§impl FromValue for u8
impl FromValue for u8
type Intermediate = ParseIrOpt<u8>
source§impl FromValue for isize
impl FromValue for isize
type Intermediate = ParseIrOpt<isize>
source§impl FromValue for u32
impl FromValue for u32
type Intermediate = ParseIrOpt<u32>
source§impl FromValue for i8
impl FromValue for i8
type Intermediate = ParseIrOpt<i8>
source§impl FromValue for u64
impl FromValue for u64
type Intermediate = ParseIrOpt<u64>
source§impl FromValue for usize
impl FromValue for usize
type Intermediate = ParseIrOpt<usize>
source§impl FromValue for i16
impl FromValue for i16
type Intermediate = ParseIrOpt<i16>
source§impl FromValue for Time
impl FromValue for Time
Converts a MySQL TIME value to a time::Time.
Note: time::Time only allows for time values in the 00:00:00 - 23:59:59 range.
If you’re expecting TIME values in MySQL’s TIME value range of -838:59:59 - 838:59:59,
use time::Duration instead.