#[repr(transparent)]pub struct Datum(_);
Expand description
Datum is an abstract value that is effectively a union of all scalar types
and all possible pointers in a Postgres context. That is, it is either
“pass-by-value” (if the value fits into the platform’s uintptr_t
) or
“pass-by-reference” (if it does not).
In Rust, it is best to treat this largely as a pointer while passing it around for code that doesn’t care about what the Datum “truly is”. If for some reason it is important to manipulate the address/value without “knowing the type” of the Datum, cast to a pointer and use pointer methods.
Only create Datums from non-pointers when you know you want to pass a value, as
it is erroneous for unsafe
code to dereference the address of “only a value” as a pointer.
It is still a “safe” operation to create such pointers: validity is asserted by dereferencing.
For all intents and purposes, however, Postgres counts as unsafe
code that may be relying
on you communicating pointers correctly to it. Do not play games with your database.
Implementations
Trait Implementations
sourceimpl FromDatum for Datum
impl FromDatum for Datum
for pg_sys::Datum
sourceunsafe fn from_datum_in_memory_context(
memory_context: PgMemoryContexts,
datum: Datum,
is_null: bool
) -> Option<Self> where
Self: Sized,
unsafe fn from_datum_in_memory_context(
memory_context: PgMemoryContexts,
datum: Datum,
is_null: bool
) -> Option<Self> where
Self: Sized,
Default implementation switched to the specified memory context and then simply calls
FromDatum::from_datum(...)
from within that context. Read more
sourceunsafe fn try_from_datum(
datum: Datum,
is_null: bool,
type_oid: Oid
) -> Result<Option<Self>, TryFromDatumError> where
Self: Sized + IntoDatum + 'static,
unsafe fn try_from_datum(
datum: Datum,
is_null: bool,
type_oid: Oid
) -> Result<Option<Self>, TryFromDatumError> where
Self: Sized + IntoDatum + 'static,
try_from_datum
is a convenience wrapper around FromDatum::from_datum
that returns a
a Result
instead of an Option
. It’s intended to be used in situations where
the caller needs to know whether the type conversion succeeded or failed. Read more
sourceimpl IntoDatum for Datum
impl IntoDatum for Datum
fn into_datum(self) -> Option<Datum>
fn type_oid() -> Oid
fn array_type_oid() -> Oid
sourcefn is_compatible_with(other: Oid) -> bool
fn is_compatible_with(other: Oid) -> bool
Is a Datum of this type compatible with another Postgres type? Read more
sourcefn is_pass_by_value() -> bool where
Self: 'static,
fn is_pass_by_value() -> bool where
Self: 'static,
Is a Datum of this type pass by value or pass by reference? Read more
impl Copy for Datum
impl StructuralPartialEq for Datum
Auto Trait Implementations
impl RefUnwindSafe for Datum
impl !Send for Datum
impl !Sync for Datum
impl Unpin for Datum
impl UnwindSafe for Datum
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
sourcefn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
impl<D> OwoColorize for D
impl<D> OwoColorize for D
fn fg<C>(&self) -> FgColorDisplay<'_, C, Self> where
C: Color,
fn fg<C>(&self) -> FgColorDisplay<'_, C, Self> where
C: Color,
Set the foreground color generically Read more
fn bg<C>(&self) -> BgColorDisplay<'_, C, Self> where
C: Color,
fn bg<C>(&self) -> BgColorDisplay<'_, C, Self> where
C: Color,
Set the background color generically. Read more
fn black(&'a self) -> FgColorDisplay<'a, Black, Self>
fn black(&'a self) -> FgColorDisplay<'a, Black, Self>
Change the foreground color to black
fn on_black(&'a self) -> BgColorDisplay<'a, Black, Self>
fn on_black(&'a self) -> BgColorDisplay<'a, Black, Self>
Change the background color to black
fn red(&'a self) -> FgColorDisplay<'a, Red, Self>
fn red(&'a self) -> FgColorDisplay<'a, Red, Self>
Change the foreground color to red
fn on_red(&'a self) -> BgColorDisplay<'a, Red, Self>
fn on_red(&'a self) -> BgColorDisplay<'a, Red, Self>
Change the background color to red
fn green(&'a self) -> FgColorDisplay<'a, Green, Self>
fn green(&'a self) -> FgColorDisplay<'a, Green, Self>
Change the foreground color to green
fn on_green(&'a self) -> BgColorDisplay<'a, Green, Self>
fn on_green(&'a self) -> BgColorDisplay<'a, Green, Self>
Change the background color to green
fn yellow(&'a self) -> FgColorDisplay<'a, Yellow, Self>
fn yellow(&'a self) -> FgColorDisplay<'a, Yellow, Self>
Change the foreground color to yellow
fn on_yellow(&'a self) -> BgColorDisplay<'a, Yellow, Self>
fn on_yellow(&'a self) -> BgColorDisplay<'a, Yellow, Self>
Change the background color to yellow
fn blue(&'a self) -> FgColorDisplay<'a, Blue, Self>
fn blue(&'a self) -> FgColorDisplay<'a, Blue, Self>
Change the foreground color to blue
fn on_blue(&'a self) -> BgColorDisplay<'a, Blue, Self>
fn on_blue(&'a self) -> BgColorDisplay<'a, Blue, Self>
Change the background color to blue
fn magenta(&'a self) -> FgColorDisplay<'a, Magenta, Self>
fn magenta(&'a self) -> FgColorDisplay<'a, Magenta, Self>
Change the foreground color to magenta
fn on_magenta(&'a self) -> BgColorDisplay<'a, Magenta, Self>
fn on_magenta(&'a self) -> BgColorDisplay<'a, Magenta, Self>
Change the background color to magenta
fn purple(&'a self) -> FgColorDisplay<'a, Magenta, Self>
fn purple(&'a self) -> FgColorDisplay<'a, Magenta, Self>
Change the foreground color to purple
fn on_purple(&'a self) -> BgColorDisplay<'a, Magenta, Self>
fn on_purple(&'a self) -> BgColorDisplay<'a, Magenta, Self>
Change the background color to purple
fn cyan(&'a self) -> FgColorDisplay<'a, Cyan, Self>
fn cyan(&'a self) -> FgColorDisplay<'a, Cyan, Self>
Change the foreground color to cyan
fn on_cyan(&'a self) -> BgColorDisplay<'a, Cyan, Self>
fn on_cyan(&'a self) -> BgColorDisplay<'a, Cyan, Self>
Change the background color to cyan
fn white(&'a self) -> FgColorDisplay<'a, White, Self>
fn white(&'a self) -> FgColorDisplay<'a, White, Self>
Change the foreground color to white
fn on_white(&'a self) -> BgColorDisplay<'a, White, Self>
fn on_white(&'a self) -> BgColorDisplay<'a, White, Self>
Change the background color to white
fn default_color(&'a self) -> FgColorDisplay<'a, Default, Self>
fn default_color(&'a self) -> FgColorDisplay<'a, Default, Self>
Change the foreground color to the terminal default
fn on_default_color(&'a self) -> BgColorDisplay<'a, Default, Self>
fn on_default_color(&'a self) -> BgColorDisplay<'a, Default, Self>
Change the background color to the terminal default
fn bright_black(&'a self) -> FgColorDisplay<'a, BrightBlack, Self>
fn bright_black(&'a self) -> FgColorDisplay<'a, BrightBlack, Self>
Change the foreground color to bright black
fn on_bright_black(&'a self) -> BgColorDisplay<'a, BrightBlack, Self>
fn on_bright_black(&'a self) -> BgColorDisplay<'a, BrightBlack, Self>
Change the background color to bright black
fn bright_red(&'a self) -> FgColorDisplay<'a, BrightRed, Self>
fn bright_red(&'a self) -> FgColorDisplay<'a, BrightRed, Self>
Change the foreground color to bright red
fn on_bright_red(&'a self) -> BgColorDisplay<'a, BrightRed, Self>
fn on_bright_red(&'a self) -> BgColorDisplay<'a, BrightRed, Self>
Change the background color to bright red
fn bright_green(&'a self) -> FgColorDisplay<'a, BrightGreen, Self>
fn bright_green(&'a self) -> FgColorDisplay<'a, BrightGreen, Self>
Change the foreground color to bright green
fn on_bright_green(&'a self) -> BgColorDisplay<'a, BrightGreen, Self>
fn on_bright_green(&'a self) -> BgColorDisplay<'a, BrightGreen, Self>
Change the background color to bright green
fn bright_yellow(&'a self) -> FgColorDisplay<'a, BrightYellow, Self>
fn bright_yellow(&'a self) -> FgColorDisplay<'a, BrightYellow, Self>
Change the foreground color to bright yellow
fn on_bright_yellow(&'a self) -> BgColorDisplay<'a, BrightYellow, Self>
fn on_bright_yellow(&'a self) -> BgColorDisplay<'a, BrightYellow, Self>
Change the background color to bright yellow
fn bright_blue(&'a self) -> FgColorDisplay<'a, BrightBlue, Self>
fn bright_blue(&'a self) -> FgColorDisplay<'a, BrightBlue, Self>
Change the foreground color to bright blue
fn on_bright_blue(&'a self) -> BgColorDisplay<'a, BrightBlue, Self>
fn on_bright_blue(&'a self) -> BgColorDisplay<'a, BrightBlue, Self>
Change the background color to bright blue
fn bright_magenta(&'a self) -> FgColorDisplay<'a, BrightMagenta, Self>
fn bright_magenta(&'a self) -> FgColorDisplay<'a, BrightMagenta, Self>
Change the foreground color to bright magenta
fn on_bright_magenta(&'a self) -> BgColorDisplay<'a, BrightMagenta, Self>
fn on_bright_magenta(&'a self) -> BgColorDisplay<'a, BrightMagenta, Self>
Change the background color to bright magenta
fn bright_purple(&'a self) -> FgColorDisplay<'a, BrightMagenta, Self>
fn bright_purple(&'a self) -> FgColorDisplay<'a, BrightMagenta, Self>
Change the foreground color to bright purple
fn on_bright_purple(&'a self) -> BgColorDisplay<'a, BrightMagenta, Self>
fn on_bright_purple(&'a self) -> BgColorDisplay<'a, BrightMagenta, Self>
Change the background color to bright purple
fn bright_cyan(&'a self) -> FgColorDisplay<'a, BrightCyan, Self>
fn bright_cyan(&'a self) -> FgColorDisplay<'a, BrightCyan, Self>
Change the foreground color to bright cyan
fn on_bright_cyan(&'a self) -> BgColorDisplay<'a, BrightCyan, Self>
fn on_bright_cyan(&'a self) -> BgColorDisplay<'a, BrightCyan, Self>
Change the background color to bright cyan
fn bright_white(&'a self) -> FgColorDisplay<'a, BrightWhite, Self>
fn bright_white(&'a self) -> FgColorDisplay<'a, BrightWhite, Self>
Change the foreground color to bright white
fn on_bright_white(&'a self) -> BgColorDisplay<'a, BrightWhite, Self>
fn on_bright_white(&'a self) -> BgColorDisplay<'a, BrightWhite, Self>
Change the background color to bright white
fn bold(&'a self) -> BoldDisplay<'a, Self>
fn bold(&'a self) -> BoldDisplay<'a, Self>
Make the text bold
fn dimmed(&'a self) -> DimDisplay<'a, Self>
fn dimmed(&'a self) -> DimDisplay<'a, Self>
Make the text dim
fn italic(&'a self) -> ItalicDisplay<'a, Self>
fn italic(&'a self) -> ItalicDisplay<'a, Self>
Make the text italicized
fn underline(&'a self) -> UnderlineDisplay<'a, Self>
fn underline(&'a self) -> UnderlineDisplay<'a, Self>
Make the text italicized
fn blink(&'a self) -> BlinkDisplay<'a, Self>
fn blink(&'a self) -> BlinkDisplay<'a, Self>
Make the text blink
fn blink_fast(&'a self) -> BlinkFastDisplay<'a, Self>
fn blink_fast(&'a self) -> BlinkFastDisplay<'a, Self>
Make the text blink (but fast!)
fn reversed(&'a self) -> ReversedDisplay<'a, Self>
fn reversed(&'a self) -> ReversedDisplay<'a, Self>
Swap the foreground and background colors
Hide the text
fn strikethrough(&'a self) -> StrikeThroughDisplay<'a, Self>
fn strikethrough(&'a self) -> StrikeThroughDisplay<'a, Self>
Cross out the text
fn color<Color>(&self, color: Color) -> FgDynColorDisplay<'_, Color, Self> where
Color: DynColor,
fn color<Color>(&self, color: Color) -> FgDynColorDisplay<'_, Color, Self> where
Color: DynColor,
Set the foreground color at runtime. Only use if you do not know which color will be used at
compile-time. If the color is constant, use either OwoColorize::fg
or
a color-specific method, such as OwoColorize::green
, Read more
fn on_color<Color>(&self, color: Color) -> BgDynColorDisplay<'_, Color, Self> where
Color: DynColor,
fn on_color<Color>(&self, color: Color) -> BgDynColorDisplay<'_, Color, Self> where
Color: DynColor,
Set the background color at runtime. Only use if you do not know what color to use at
compile-time. If the color is constant, use either OwoColorize::bg
or
a color-specific method, such as OwoColorize::on_yellow
, Read more
fn fg_rgb<const R: u8, const G: u8, const B: u8>(
&self
) -> FgColorDisplay<'_, CustomColor<R, G, B>, Self>
fn fg_rgb<const R: u8, const G: u8, const B: u8>(
&self
) -> FgColorDisplay<'_, CustomColor<R, G, B>, Self>
Set the foreground color to a specific RGB value.
fn bg_rgb<const R: u8, const G: u8, const B: u8>(
&self
) -> BgColorDisplay<'_, CustomColor<R, G, B>, Self>
fn bg_rgb<const R: u8, const G: u8, const B: u8>(
&self
) -> BgColorDisplay<'_, CustomColor<R, G, B>, Self>
Set the background color to a specific RGB value.
fn truecolor(&self, r: u8, g: u8, b: u8) -> FgDynColorDisplay<'_, Rgb, Self>
fn truecolor(&self, r: u8, g: u8, b: u8) -> FgDynColorDisplay<'_, Rgb, Self>
Sets the foreground color to an RGB value.
fn on_truecolor(&self, r: u8, g: u8, b: u8) -> BgDynColorDisplay<'_, Rgb, Self>
fn on_truecolor(&self, r: u8, g: u8, b: u8) -> BgDynColorDisplay<'_, Rgb, Self>
Sets the background color to an RGB value.
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
fn vzip(self) -> V
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more