#[repr(transparent)]pub struct Pattern<B: PatternBackend> {
pub store: B::Store,
/* private fields */
}
Expand description
A string pattern with placeholders.
There are 2 generic parameters: Backend
and Store
.
§Backend
This determines the nature of placeholders and serialized encoding of the pattern.
The following backends are available:
SinglePlaceholder
for patterns with up to one placeholder:"{0} days ago"
DoublePlaceholder
for patterns with up to two placeholders:"{0} days, {1} hours ago"
MultiNamedPlaceholder
for patterns with named placeholders:"{name} sent you a message"
§Format to Parts
Pattern
propagates Part
s from inner writeables. In addition, it supports annotating
Part
s for individual literals or placeholders via the PlaceholderValueProvider
trait.
§Examples
Interpolating a SinglePlaceholder
pattern:
use core::str::FromStr;
use icu_pattern::Pattern;
use icu_pattern::SinglePlaceholder;
use writeable::assert_writeable_eq;
let pattern = Pattern::<SinglePlaceholder>::try_from_str(
"Hello, {0}!",
Default::default(),
)
.unwrap();
assert_writeable_eq!(pattern.interpolate(["Alice"]), "Hello, Alice!");
Fields§
§store: B::Store
The encoded storage
Implementations§
Source§impl<B> Pattern<B>where
B: PatternBackend,
impl<B> Pattern<B>where
B: PatternBackend,
Sourcepub fn try_from_items<'a, I>(items: I) -> Result<Box<Self>, Error>
pub fn try_from_items<'a, I>(items: I) -> Result<Box<Self>, Error>
Creates a pattern from an iterator of pattern items.
✨ Enabled with the alloc
Cargo feature.
§Examples
use icu_pattern::Pattern;
use icu_pattern::PatternItemCow;
use icu_pattern::SinglePlaceholder;
use icu_pattern::SinglePlaceholderKey;
use std::borrow::Cow;
Pattern::<SinglePlaceholder>::try_from_items(
[
PatternItemCow::Placeholder(SinglePlaceholderKey::Singleton),
PatternItemCow::Literal(Cow::Borrowed(" days")),
]
.into_iter(),
)
.expect("valid pattern items");
Source§impl<'a, B> Pattern<B>where
B: PatternBackend,
B::PlaceholderKeyCow<'a>: FromStr,
<B::PlaceholderKeyCow<'a> as FromStr>::Err: Debug,
impl<'a, B> Pattern<B>where
B: PatternBackend,
B::PlaceholderKeyCow<'a>: FromStr,
<B::PlaceholderKeyCow<'a> as FromStr>::Err: Debug,
Sourcepub fn try_from_str(
pattern: &str,
options: ParserOptions,
) -> Result<Box<Self>, Error>
pub fn try_from_str( pattern: &str, options: ParserOptions, ) -> Result<Box<Self>, Error>
Creates a pattern by parsing a syntax string.
✨ Enabled with the alloc
Cargo feature.
§Examples
use icu_pattern::Pattern;
use icu_pattern::SinglePlaceholder;
// Create a pattern from a valid string:
Pattern::<SinglePlaceholder>::try_from_str("{0} days", Default::default())
.expect("valid pattern");
// Error on an invalid pattern:
Pattern::<SinglePlaceholder>::try_from_str("{0 days", Default::default())
.expect_err("mismatched braces");
Source§impl<B> Pattern<B>where
B: PatternBackend,
impl<B> Pattern<B>where
B: PatternBackend,
Sourcepub fn iter(
&self,
) -> impl Iterator<Item = PatternItem<'_, B::PlaceholderKey<'_>>> + '_
pub fn iter( &self, ) -> impl Iterator<Item = PatternItem<'_, B::PlaceholderKey<'_>>> + '_
Returns an iterator over the PatternItem
s in this pattern.
Sourcepub fn try_interpolate<'a, P>(
&'a self,
value_provider: P,
) -> impl TryWriteable<Error = B::Error<'a>> + Display + 'a
pub fn try_interpolate<'a, P>( &'a self, value_provider: P, ) -> impl TryWriteable<Error = B::Error<'a>> + Display + 'a
Returns a TryWriteable
that interpolates items from the given replacement provider
into this pattern string.
Sourcepub fn try_interpolate_to_string<'a, P>(
&'a self,
value_provider: P,
) -> Result<String, (B::Error<'a>, String)>
pub fn try_interpolate_to_string<'a, P>( &'a self, value_provider: P, ) -> Result<String, (B::Error<'a>, String)>
Interpolates the pattern directly to a string, returning the string or an error.
In addition to the error, the lossy fallback string is returned in the failure case.
✨ Enabled with the alloc
Cargo feature.
Source§impl<B> Pattern<B>where
for<'b> B: PatternBackend<Error<'b> = Infallible>,
impl<B> Pattern<B>where
for<'b> B: PatternBackend<Error<'b> = Infallible>,
Sourcepub fn interpolate<'a, P>(
&'a self,
value_provider: P,
) -> impl Writeable + Display + 'a
pub fn interpolate<'a, P>( &'a self, value_provider: P, ) -> impl Writeable + Display + 'a
Returns a Writeable
that interpolates items from the given replacement provider
into this pattern string.
Sourcepub fn interpolate_to_string<'a, P>(&'a self, value_provider: P) -> String
pub fn interpolate_to_string<'a, P>(&'a self, value_provider: P) -> String
Interpolates the pattern directly to a string.
✨ Enabled with the alloc
Cargo feature.
Trait Implementations§
Source§impl<B: PatternBackend> Debug for Pattern<B>
impl<B: PatternBackend> Debug for Pattern<B>
Source§impl<B: PatternBackend> Default for &'static Pattern<B>
impl<B: PatternBackend> Default for &'static Pattern<B>
Source§impl<'de, 'data, B: PatternBackend> Deserialize<'de> for &'data Pattern<B>where
&'data B::Store: Deserialize<'de>,
'de: 'data,
impl<'de, 'data, B: PatternBackend> Deserialize<'de> for &'data Pattern<B>where
&'data B::Store: Deserialize<'de>,
'de: 'data,
Source§fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
Source§impl<'de, 'data, B> Deserialize<'de> for Box<Pattern<B>>
impl<'de, 'data, B> Deserialize<'de> for Box<Pattern<B>>
Source§fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
Source§impl<B: PatternBackend> PartialEq for Pattern<B>
impl<B: PatternBackend> PartialEq for Pattern<B>
Source§impl<B: PatternBackend> Serialize for Pattern<B>where
B::Store: Serialize,
for<'a> B::PlaceholderKeyCow<'a>: Serialize + From<B::PlaceholderKey<'a>>,
impl<B: PatternBackend> Serialize for Pattern<B>where
B::Store: Serialize,
for<'a> B::PlaceholderKeyCow<'a>: Serialize + From<B::PlaceholderKey<'a>>,
Source§impl<B: PatternBackend> ToOwned for Pattern<B>
impl<B: PatternBackend> ToOwned for Pattern<B>
Source§impl<B, S: ?Sized + VarULE> VarULE for Pattern<B>where
B: PatternBackend<Store = S>,
Implement VarULE
for Pattern<SinglePlaceholder, str>
.
impl<B, S: ?Sized + VarULE> VarULE for Pattern<B>where
B: PatternBackend<Store = S>,
Implement VarULE
for Pattern<SinglePlaceholder, str>
.
§Safety
Safety checklist for ULE
:
Pattern<B>
does not include any uninitialized or padding bytes.Pattern<B>
is aligned to 1 byte.- The implementation of
validate_bytes()
returns an error if any byte is not valid. - The implementation of
validate_bytes()
returns an error if the slice cannot be used to build aPattern<B>
in its entirety. - The implementation of
from_bytes_unchecked()
returns a reference to the same data. parse_bytes()
is equivalent tovalidate_bytes()
followed byfrom_bytes_unchecked()
.Pattern<B>
byte equality is semantic equality.
Source§fn validate_bytes(bytes: &[u8]) -> Result<(), UleError>
fn validate_bytes(bytes: &[u8]) -> Result<(), UleError>
&[u8]
. Read moreSource§unsafe fn from_bytes_unchecked(bytes: &[u8]) -> &Self
unsafe fn from_bytes_unchecked(bytes: &[u8]) -> &Self
&[u8]
, and return it as &Self
with the same lifetime, assuming
that this byte slice has previously been run through Self::parse_bytes()
with
success. Read moreSource§impl<'a, B: PatternBackend> ZeroMapKV<'a> for Pattern<B>
impl<'a, B: PatternBackend> ZeroMapKV<'a> for Pattern<B>
Source§type Container = VarZeroVec<'a, Pattern<B>>
type Container = VarZeroVec<'a, Pattern<B>>
ZeroVec
or VarZeroVec
.type Slice = VarZeroSlice<Pattern<B>>
Auto Trait Implementations§
impl<B> Freeze for Pattern<B>
impl<B> RefUnwindSafe for Pattern<B>
impl<B> Send for Pattern<B>
impl<B> Sync for Pattern<B>
impl<B> Unpin for Pattern<B>
impl<B> UnwindSafe for Pattern<B>
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> EncodeAsVarULE<T> for T
impl<T> EncodeAsVarULE<T> for T
Source§fn encode_var_ule_as_slices<R>(&self, cb: impl FnOnce(&[&[u8]]) -> R) -> R
fn encode_var_ule_as_slices<R>(&self, cb: impl FnOnce(&[&[u8]]) -> R) -> R
cb
with a piecewise list of byte slices that when concatenated
produce the memory pattern of the corresponding instance of T
. Read moreSource§fn encode_var_ule_len(&self) -> usize
fn encode_var_ule_len(&self) -> usize
VarULE
typeSource§fn encode_var_ule_write(&self, dst: &mut [u8])
fn encode_var_ule_write(&self, dst: &mut [u8])
VarULE
type to the dst
buffer. dst
should
be the size of Self::encode_var_ule_len()
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read more