Enum lexpr::Atom

pub enum Atom {
    Nil,
    Bool(bool),
    Number(Number),
    String(String),
    Symbol(String),
    Keyword(String),
}

A Lisp atom.

Atoms represent non-compound data types.

Variants

Nil

The special "nil" value.

This value is used in many Lisp dialects to represent the empty list. It is different from the empty list in lexpr; the latter is represented as a Value::List with zero elements.

Bool(bool)

A boolean value.

Number(Number)

A number.

String(String)

A string.

Symbol(String)

A symbol.

Keyword(String)

A keyword.

Methods

impl Atom

pub fn symbol(name: impl Into<String>) -> Self

Create an atom representing a symbol.

pub fn keyword(name: impl Into<String>) -> Self

Create an atom representing a keyword.

pub fn is_nil(&self) -> bool

Check whether the atom is the special nil value.

pub fn as_nil(&self) -> Option<()>

If the atom is nil, returns (). Returns None otherwise.

pub fn is_string(&self) -> bool

Check wether the atom represents a string.

pub fn as_str(&self) -> Option<&str>

If the atom represents a string, return it as str reference. Returns None otherwise.

pub fn is_symbol(&self) -> bool

Check wether the atom represents a symbol.

pub fn as_symbol(&self) -> Option<&str>

If the atom represents a symbol, return it as str reference. Returns None otherwise.

pub fn is_keyword(&self) -> bool

Check wether the atom represents a keyword.

pub fn as_keyword(&self) -> Option<&str>

If the atom represents a keyword, return it as str reference. Returns None otherwise.

pub fn is_boolean(&self) -> bool

Check wether the atom represents a boolean value.

pub fn as_bool(&self) -> Option<bool>

If the atom is a boolean, return its value.

pub fn as_name(&self) -> Option<&str>

Get the name of a symbol or keyword, or the value of a string.

pub fn is_i64(&self) -> bool

Check whether the atom is an integer and can be represented as an i64.

pub fn as_i64(&self) -> Option<i64>

If the atom is an integer, represent it as an i64, if possible.

pub fn is_u64(&self) -> bool

Check whether the atom is an integer and can be represented as an u64.

pub fn as_u64(&self) -> Option<u64>

If the atom is an integer, represent it as an u64, if possible.

pub fn is_f64(&self) -> bool

Check whether the atom is a floating point number and can be represented as an f64.

Currently this function returns true if and only if both is_i64 and is_u64 return false but this is not a guarantee in the future.

pub fn as_f64(&self) -> Option<f64>

If the atom is a number, represent it as an f64, if possible.

pub fn as_number(&self) -> Option<&Number>

If the atom is a number, return a reference to the underlying Number instance.

Trait Implementations

impl PartialEq<Atom> for Atom

fn eq(&self, other: &Atom) -> bool

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

fn ne(&self, other: &Atom) -> bool

This method tests for !=.

impl Clone for Atom

fn clone(&self) -> Atom

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl From<Atom> for Value

fn from(atom: Atom) -> Self

Performs the conversion.

impl From<u8> for Atom

fn from(n: u8) -> Self

Performs the conversion.

impl From<u16> for Atom

fn from(n: u16) -> Self

Performs the conversion.

impl From<u32> for Atom

fn from(n: u32) -> Self

Performs the conversion.

impl From<u64> for Atom

fn from(n: u64) -> Self

Performs the conversion.

impl From<i8> for Atom

fn from(n: i8) -> Self

Performs the conversion.

impl From<i16> for Atom

fn from(n: i16) -> Self

Performs the conversion.

impl From<i32> for Atom

fn from(n: i32) -> Self

Performs the conversion.

impl From<i64> for Atom

fn from(n: i64) -> Self

Performs the conversion.

impl From<f32> for Atom

fn from(n: f32) -> Self

Performs the conversion.

impl From<f64> for Atom

fn from(n: f64) -> Self

Performs the conversion.

impl<'_> From<&'_ str> for Atom

fn from(s: &str) -> Self

Performs the conversion.

impl<'a> From<Cow<'a, str>> for Atom

fn from(s: Cow<'a, str>) -> Self

Performs the conversion.

impl From<String> for Atom

fn from(s: String) -> Self

Performs the conversion.

impl From<bool> for Atom

fn from(v: bool) -> Self

Performs the conversion.

impl From<Number> for Atom

fn from(n: Number) -> Self

Performs the conversion.

impl Debug for Atom

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.