Struct frame_support::dispatch::fmt::DebugMap
1.2.0 · source · pub struct DebugMap<'a, 'b>where
'b: 'a,{ /* private fields */ }
Expand description
A struct to help with fmt::Debug
implementations.
This is useful when you wish to output a formatted map as a part of your
Debug::fmt
implementation.
This can be constructed by the Formatter::debug_map
method.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
fmt.debug_map().entries(self.0.iter().map(|&(ref k, ref v)| (k, v))).finish()
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"A\": 10, \"B\": 11}",
);
Implementations
sourceimpl<'a, 'b> DebugMap<'a, 'b>where
'b: 'a,
impl<'a, 'b> DebugMap<'a, 'b>where
'b: 'a,
sourcepub fn entry(
&mut self,
key: &dyn Debug,
value: &dyn Debug
) -> &mut DebugMap<'a, 'b>
pub fn entry(
&mut self,
key: &dyn Debug,
value: &dyn Debug
) -> &mut DebugMap<'a, 'b>
Adds a new entry to the map output.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map()
.entry(&"whole", &self.0) // We add the "whole" entry.
.finish()
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"whole\": [(\"A\", 10), (\"B\", 11)]}",
);
1.42.0 · sourcepub fn key(&mut self, key: &dyn Debug) -> &mut DebugMap<'a, 'b>
pub fn key(&mut self, key: &dyn Debug) -> &mut DebugMap<'a, 'b>
Adds the key part of a new entry to the map output.
This method, together with value
, is an alternative to entry
that
can be used when the complete entry isn’t known upfront. Prefer the entry
method when it’s possible to use.
Panics
key
must be called before value
and each call to key
must be followed
by a corresponding call to value
. Otherwise this method will panic.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map()
.key(&"whole").value(&self.0) // We add the "whole" entry.
.finish()
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"whole\": [(\"A\", 10), (\"B\", 11)]}",
);
1.42.0 · sourcepub fn value(&mut self, value: &dyn Debug) -> &mut DebugMap<'a, 'b>
pub fn value(&mut self, value: &dyn Debug) -> &mut DebugMap<'a, 'b>
Adds the value part of a new entry to the map output.
This method, together with key
, is an alternative to entry
that
can be used when the complete entry isn’t known upfront. Prefer the entry
method when it’s possible to use.
Panics
key
must be called before value
and each call to key
must be followed
by a corresponding call to value
. Otherwise this method will panic.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map()
.key(&"whole").value(&self.0) // We add the "whole" entry.
.finish()
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"whole\": [(\"A\", 10), (\"B\", 11)]}",
);
sourcepub fn entries<K, V, I>(&mut self, entries: I) -> &mut DebugMap<'a, 'b>where
K: Debug,
V: Debug,
I: IntoIterator<Item = (K, V)>,
pub fn entries<K, V, I>(&mut self, entries: I) -> &mut DebugMap<'a, 'b>where
K: Debug,
V: Debug,
I: IntoIterator<Item = (K, V)>,
Adds the contents of an iterator of entries to the map output.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map()
// We map our vec so each entries' first field will become
// the "key".
.entries(self.0.iter().map(|&(ref k, ref v)| (k, v)))
.finish()
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"A\": 10, \"B\": 11}",
);
sourcepub fn finish(&mut self) -> Result<(), Error>
pub fn finish(&mut self) -> Result<(), Error>
Finishes output and returns any error encountered.
Panics
key
must be called before value
and each call to key
must be followed
by a corresponding call to value
. Otherwise this method will panic.
Examples
use std::fmt;
struct Foo(Vec<(String, i32)>);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map()
.entries(self.0.iter().map(|&(ref k, ref v)| (k, v)))
.finish() // Ends the struct formatting.
}
}
assert_eq!(
format!("{:?}", Foo(vec![("A".to_string(), 10), ("B".to_string(), 11)])),
"{\"A\": 10, \"B\": 11}",
);
Trait Implementations
sourceimpl<'a, 'b> Visit for DebugMap<'a, 'b>
impl<'a, 'b> Visit for DebugMap<'a, 'b>
sourcefn record_debug(&mut self, field: &Field, value: &dyn Debug)
fn record_debug(&mut self, field: &Field, value: &dyn Debug)
fmt::Debug
.sourcefn record_f64(&mut self, field: &Field, value: f64)
fn record_f64(&mut self, field: &Field, value: f64)
sourcefn record_i64(&mut self, field: &Field, value: i64)
fn record_i64(&mut self, field: &Field, value: i64)
sourcefn record_u64(&mut self, field: &Field, value: u64)
fn record_u64(&mut self, field: &Field, value: u64)
sourcefn record_i128(&mut self, field: &Field, value: i128)
fn record_i128(&mut self, field: &Field, value: i128)
sourcefn record_u128(&mut self, field: &Field, value: u128)
fn record_u128(&mut self, field: &Field, value: u128)
sourcefn record_bool(&mut self, field: &Field, value: bool)
fn record_bool(&mut self, field: &Field, value: bool)
sourcefn record_str(&mut self, field: &Field, value: &str)
fn record_str(&mut self, field: &Field, value: &str)
sourcefn record_error(&mut self, field: &Field, value: &(dyn Error + 'static))
fn record_error(&mut self, field: &Field, value: &(dyn Error + 'static))
Error
. Read moreAuto Trait Implementations
impl<'a, 'b> !RefUnwindSafe for DebugMap<'a, 'b>
impl<'a, 'b> !Send for DebugMap<'a, 'b>
impl<'a, 'b> !Sync for DebugMap<'a, 'b>
impl<'a, 'b> Unpin for DebugMap<'a, 'b>where
'b: 'a,
impl<'a, 'b> !UnwindSafe for DebugMap<'a, 'b>
Blanket Implementations
sourceimpl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
sourceimpl<T> CheckedConversion for T
impl<T> CheckedConversion for T
sourcefn checked_from<T>(t: T) -> Option<Self>where
Self: TryFrom<T>,
fn checked_from<T>(t: T) -> Option<Self>where
Self: TryFrom<T>,
sourcefn checked_into<T>(self) -> Option<T>where
Self: TryInto<T>,
fn checked_into<T>(self) -> Option<T>where
Self: TryInto<T>,
impl<T> Downcast for Twhere
T: Any,
impl<T> Downcast for Twhere
T: Any,
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
. Read morefn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
. Read morefn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
&Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s. Read morefn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
&mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s. Read moresourceimpl<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>
sourceimpl<T, Outer> IsWrappedBy<Outer> for Twhere
Outer: AsRef<T> + AsMut<T> + From<T>,
T: From<Outer>,
impl<T, Outer> IsWrappedBy<Outer> for Twhere
Outer: AsRef<T> + AsMut<T> + From<T>,
T: From<Outer>,
impl<T> Pointable for T
impl<T> Pointable for T
sourceimpl<T> SaturatedConversion for T
impl<T> SaturatedConversion for T
sourcefn saturated_from<T>(t: T) -> Selfwhere
Self: UniqueSaturatedFrom<T>,
fn saturated_from<T>(t: T) -> Selfwhere
Self: UniqueSaturatedFrom<T>,
sourcefn saturated_into<T>(self) -> Twhere
Self: UniqueSaturatedInto<T>,
fn saturated_into<T>(self) -> Twhere
Self: UniqueSaturatedInto<T>,
T
. Read moresourceimpl<S, T> UncheckedInto<T> for Swhere
T: UncheckedFrom<S>,
impl<S, T> UncheckedInto<T> for Swhere
T: UncheckedFrom<S>,
sourcefn unchecked_into(self) -> T
fn unchecked_into(self) -> T
unchecked_from
.sourceimpl<T, S> UniqueSaturatedInto<T> for Swhere
T: Bounded,
S: TryInto<T>,
impl<T, S> UniqueSaturatedInto<T> for Swhere
T: Bounded,
S: TryInto<T>,
sourcefn unique_saturated_into(self) -> T
fn unique_saturated_into(self) -> T
T
.