pub(crate) enum MetaVarExpr {
    Count(IdentOption<usize>),
    Ignore(Ident),
    Index(usize),
    Length(usize),
}
Expand description

A meta-variable expression, for expansions based on properties of meta-variables.

Variants

Count(IdentOption<usize>)

The number of repetitions of an identifier, optionally limited to a number of outer-most repetition depths. If the depth limit is None then the depth is unlimited.

Ignore(Ident)

Ignore a meta-variable for repetition without expansion.

Index(usize)

The index of the repetition at a particular depth, where 0 is the inner-most repetition. The usize is the depth.

Length(usize)

The length of the repetition at a particular depth, where 0 is the inner-most repetition. The usize is the depth.

Implementations

Attempt to parse a meta-variable expression from a token stream.

Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.

Size: 32 bytes

Size for each variant:

  • Count: 32 bytes
  • Ignore: 20 bytes
  • Index: 16 bytes
  • Length: 16 bytes