# Enum syn::ConstExpr [−] [src]

    pub enum ConstExpr {
        Call(Box<ConstExpr>, Vec<ConstExpr>),
        Binary(BinOp, Box<ConstExpr>, Box<ConstExpr>),
        Unary(UnOp, Box<ConstExpr>),
        Lit(Lit),
        Cast(Box<ConstExpr>, Box<Ty>),
        Path(Path),
        Index(Box<ConstExpr>, Box<ConstExpr>),
        Paren(Box<ConstExpr>),
        Other(Other),
    }

## Variants

`Call(Box<ConstExpr>, Vec<ConstExpr>)`

A function call

The first field resolves to the function itself, and the second field is the list of arguments

`Binary(BinOp, Box<ConstExpr>, Box<ConstExpr>)`

A binary operation (For example: `a + b`, `a * b`)

`Unary(UnOp, Box<ConstExpr>)`

A unary operation (For example: `!x`, `*x`)

`Lit(Lit)`

A literal (For example: `1`, `"foo"`)

`Cast(Box<ConstExpr>, Box<Ty>)`

A cast (`foo as f64`)

`Path(Path)`

Variable reference, possibly containing `::` and/or type parameters, e.g. foo::bar::<baz>.

`Index(Box<ConstExpr>, Box<ConstExpr>)`

An indexing operation (`foo[2]`)

`Paren(Box<ConstExpr>)`

No-op: used solely so we can pretty-print faithfully

`Other(Other)`

If compiling with full support for expression syntax, any expression is allowed

## Trait Implementations

### `impl ToTokens for ConstExpr`
[src]

#### `fn to_tokens(&self, tokens: &mut Tokens)`
[src]

Write `self` to the given `Tokens`. Read more

### `impl Debug for ConstExpr`
[src]

#### `fn fmt(&self, __arg_0: &mut Formatter) -> Result`
[src]

Formats the value using the given formatter. Read more

### `impl Clone for ConstExpr`
[src]

#### `fn clone(&self) -> ConstExpr`
[src]

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`
1.0.0
[src]

Performs copy-assignment from `source`. Read more

### `impl Eq for ConstExpr`
[src]

### `impl PartialEq for ConstExpr`
[src]

#### `fn eq(&self, __arg_0: &ConstExpr) -> bool`
[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `fn ne(&self, __arg_0: &ConstExpr) -> bool`
[src]

This method tests for `!=`.

### `impl Hash for ConstExpr`
[src]

#### `fn hash<__H: Hasher>(&self, __arg_0: &mut __H)`
[src]

Feeds this value into the given [`Hasher`]. Read more

#### `fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,`
1.3.0
[src]

Feeds a slice of this type into the given [`Hasher`]. Read more

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