Enum tinyjson::JsonValue

pub enum JsonValue {
    Number(f64),
    Boolean(bool),
    String(String),
    Null,
    Array(Vec<JsonValue>),
    Object(HashMap<String, JsonValue>),
}

Enum to represent one JSON value. Each variant represents corresponding JSON types.

use tinyjson::JsonValue;
use std::convert::TryInto;

// Convert from raw values using `From` trait
let value = JsonValue::from("this is string".to_string());

// Get reference to inner value
let maybe_number: Option<&f64> = value.get();
assert!(maybe_number.is_none());
let maybe_string: Option<&String> = value.get();
assert!(maybe_string.is_some());

// Check type of JSON value
assert!(matches!(value, JsonValue::String(_)));
assert!(value.is_string());

// Convert into raw values using `TryInto` trait
let original_value: String = value.try_into().unwrap();

Variants

Number(f64)

Number type value.

Boolean(bool)

Boolean type value.

String(String)

String type value.

Null

Null type value.

Array(Vec<JsonValue>)

Array type value.

Object(HashMap<String, JsonValue>)

Object type value.

Implementations

impl JsonValue

pub fn get<T: InnerAsRef>(&self) -> Option<&T>

Get immutable reference to the inner value.

use tinyjson::JsonValue;

let value: JsonValue = "[1, 2, 3]".parse().unwrap();
let vec: &Vec<_> = value.get().unwrap();
assert_eq!(vec[0], JsonValue::from(1.0));

// Try to convert with incorrect type
assert!(value.get::<f64>().is_none());

pub fn get_mut<T: InnerAsRefMut>(&mut self) -> Option<&mut T>

Get mutable reference to the inner value.

use tinyjson::JsonValue;

let mut value: JsonValue = "[1, 2, 3]".parse().unwrap();
let vec: &mut Vec<_> = value.get_mut().unwrap();
vec[0] = JsonValue::from(false);
assert_eq!(value.stringify().unwrap(), "[false,2,3]");

// Try to convert with incorrect type
assert!(value.get_mut::<f64>().is_none());

pub fn is_bool(&self) -> bool

Check if the inner value is a boolean.

use tinyjson::JsonValue;

let v = JsonValue::from(true);
assert!(v.is_bool());
let v = JsonValue::from(1.0);
assert!(!v.is_bool());

pub fn is_number(&self) -> bool

Check if the inner value is a number.

use tinyjson::JsonValue;

let v = JsonValue::from(1.0);
assert!(v.is_number());
let v = JsonValue::from(false);
assert!(!v.is_number());

pub fn is_string(&self) -> bool

Check if the inner value is a string.

use tinyjson::JsonValue;

let v = JsonValue::from("foo".to_string());
assert!(v.is_string());
let v = JsonValue::from(1.0);
assert!(!v.is_string());

pub fn is_null(&self) -> bool

Check if the inner value is null.

use tinyjson::JsonValue;

let v = JsonValue::from(()); // () is inner representation of null value
assert!(v.is_null());
let v = JsonValue::from(false);
assert!(!v.is_null());

pub fn is_array(&self) -> bool

Check if the inner value is an array.

use tinyjson::JsonValue;

let v = JsonValue::from(vec![]);
assert!(v.is_array());
let v = JsonValue::from(1.0);
assert!(!v.is_array());

pub fn is_object(&self) -> bool

Check if the inner value is an object.

use tinyjson::JsonValue;
use std::collections::HashMap;

let v = JsonValue::from(HashMap::new());
assert!(v.is_object());
let v = JsonValue::from(vec![]);
assert!(!v.is_object());

pub fn stringify(&self) -> JsonGenerateResult

Convert this JSON value to String value.

use tinyjson::JsonValue;

let v = JsonValue::from(vec![1.0.into(), true.into(), "str".to_string().into()]);
let s = v.stringify().unwrap();
assert_eq!(&s, "[1,true,\"str\"]");

pub fn write_to<W: Write>(&self, w: &mut W) -> Result<()>

Write this JSON value to the given io::Write object as UTF-8 byte sequence.

use tinyjson::JsonValue;
use std::io::Write;

let v = JsonValue::from(vec![1.0.into(), true.into(), "str".to_string().into()]);
let mut bytes = vec![];
v.write_to(&mut bytes).unwrap();
assert_eq!(&String::from_utf8(bytes).unwrap(), "[1,true,\"str\"]");

pub fn format(&self) -> JsonGenerateResult

Convert this JSON value to String value with 2-spaces indentation.

use tinyjson::JsonValue;

let v = JsonValue::from(vec![1.0.into(), true.into(), "str".to_string().into()]);
let s = v.format().unwrap();
assert_eq!(&s,
"[
  1,
  true,
  \"str\"
]");

pub fn format_to<W: Write>(&self, w: &mut W) -> Result<()>

Write this JSON value to the given io::Write object as UTF-8 byte sequence with 2-spaces indentation.

use tinyjson::JsonValue;

let v = JsonValue::from(vec![1.0.into(), true.into(), "str".to_string().into()]);
let mut bytes = vec![];
v.format_to(&mut bytes).unwrap();
assert_eq!(&String::from_utf8(bytes).unwrap(),
"[
  1,
  true,
  \"str\"
]");

Trait Implementations

impl Clone for JsonValue

fn clone(&self) -> JsonValue

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for JsonValue

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

Formats the value using the given formatter.

impl From<()> for JsonValue

Convert () into JsonValue. () is an inner representation of null JSON value.

use tinyjson::JsonValue;
let v = JsonValue::from(());
assert!(v.is_null());

fn from(_x: ()) -> JsonValue

Converts to this type from the input type.

impl From<HashMap<String, JsonValue, RandomState>> for JsonValue

Convert HashMap value into JsonValue.

use tinyjson::JsonValue;
use std::collections::HashMap;
let mut m = HashMap::new();
m.insert("foo".to_string(), 1.0.into());
let v = JsonValue::from(m);
assert!(v.is_object());

fn from(o: HashMap<String, JsonValue>) -> JsonValue

Converts to this type from the input type.

impl From<String> for JsonValue

Convert bool value into JsonValue. Note that &str is not available. Explicitly allocate String object and pass it.

use tinyjson::JsonValue;
let v = JsonValue::from("foo".to_string());
assert!(v.is_string());

fn from(s: String) -> JsonValue

Converts to this type from the input type.

impl From<UnexpectedValue> for JsonValue

Convert this error into the value which failed to be converted.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let error = String::try_from(JsonValue::from(1.0)).unwrap_err();
assert_eq!(JsonValue::from(error), JsonValue::Number(1.0));

fn from(err: UnexpectedValue) -> Self

Converts to this type from the input type.

impl From<Vec<JsonValue, Global>> for JsonValue

Convert Vec value into JsonValue.

use tinyjson::JsonValue;
let v = JsonValue::from(vec![1.0.into(), true.into()]);
assert!(v.is_array());

fn from(a: Vec<JsonValue>) -> JsonValue

Converts to this type from the input type.

impl From<bool> for JsonValue

Convert bool value into JsonValue.

use tinyjson::JsonValue;
let v = JsonValue::from(true);
assert!(v.is_bool());

fn from(b: bool) -> JsonValue

Converts to this type from the input type.

impl From<f64> for JsonValue

Convert f64 value into JsonValue.

use tinyjson::JsonValue;
let v = JsonValue::from(1.0);
assert!(v.is_number());

fn from(n: f64) -> JsonValue

Converts to this type from the input type.

impl FromStr for JsonValue

Parse given str object into JsonValue value. This is recommended way to parse strings into JSON value with this library.

use tinyjson::JsonValue;

let array: JsonValue = "[1, 2, 3]".parse().unwrap();
assert!(array.is_array());

type Err = JsonParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl<'a> Index<&'a str> for JsonValue

Access to value of the key of object.

use tinyjson::JsonValue;
use std::collections::HashMap;

let mut m = HashMap::new();
m.insert("foo".to_string(), 1.0.into());
let v = JsonValue::from(m);
let i = &v["foo"];
assert_eq!(i, &JsonValue::Number(1.0));

This will panic when the given JsonValue value is not an object

let v = JsonValue::from(vec![]);
let _ = &v["foo"]; // Panic

or when the key does not exist in the object.

let v = JsonValue::from(HashMap::new());
let _ = &v["foo"]; // Panic

Using this operator, you can access the nested elements quickly

let mut json: JsonValue = r#"
{
  "foo": {
    "bar": [
      { "target": 42 }
    ]
  }
}
"#.parse().unwrap();

// Access with index operator
let target_value: f64 = *json["foo"]["bar"][0]["target"].get().unwrap();
assert_eq!(target_value, 42.0);

type Output = JsonValue

The returned type after indexing.

fn index(&self, key: &'a str) -> &Self::Output

Performs the indexing (container[index]) operation.

impl Index<usize> for JsonValue

Access to value of the index of array.

use tinyjson::JsonValue;

let v = JsonValue::from(vec![1.0.into(), true.into()]);
let b = &v[1];
assert_eq!(b, &JsonValue::Boolean(true));

This will panic when the given JsonValue value is not an array

use std::collections::HashMap;
let v = JsonValue::from(HashMap::new());
let _ = &v[0]; // Panic

or when the index is out of bounds.

let v = JsonValue::from(vec![]);
let _ = &v[0]; // Panic

type Output = JsonValue

The returned type after indexing.

fn index(&self, index: usize) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<'a> IndexMut<&'a str> for JsonValue

Access to value of the key of mutable object.

use tinyjson::JsonValue;
use std::collections::HashMap;

let mut m = HashMap::new();
m.insert("foo".to_string(), 1.0.into());
let mut v = JsonValue::from(m);
v["foo"] = JsonValue::Number(3.14);
assert_eq!(v["foo"], JsonValue::Number(3.14));

This will panic when the given JsonValue value is not an object

let mut v = JsonValue::from(vec![]);
let _ = &mut v["foo"]; // Panic

or when the key does not exist in the object.

let mut v = JsonValue::from(HashMap::new());
let _ = &mut v["foo"]; // Panic

Using this operator, you can modify the nested elements quickly

let mut json: JsonValue = r#"
{
  "foo": {
    "bar": [
      { "target": 42 }
    ]
  }
}
"#.parse().unwrap();

// Modify with index operator
json["foo"]["bar"][0]["target"] = JsonValue::Boolean(false);
assert_eq!(json["foo"]["bar"][0]["target"], JsonValue::Boolean(false));

fn index_mut(&mut self, key: &'a str) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl IndexMut<usize> for JsonValue

Access to value of the index of mutable array.

use tinyjson::JsonValue;

let mut v = JsonValue::from(vec![1.0.into(), true.into()]);
let b = &mut v[1];
assert_eq!(b, &JsonValue::Boolean(true));

This will panic when the given JsonValue value is not an array

use std::collections::HashMap;
let mut v = JsonValue::from(HashMap::new());
let _ = &mut v[0]; // Panic

or when the index is out of bounds.

let mut v = JsonValue::from(vec![]);
let _ = &mut v[0]; // Panic

fn index_mut(&mut self, index: usize) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl PartialEq<JsonValue> for JsonValue

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

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

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TryFrom<JsonValue> for ()

Try to convert the JsonValue value into (). Note that () is an inner representation of null JSON value. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let v = JsonValue::from(());
let r = <()>::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(1.0);
let r = <()>::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl TryFrom<JsonValue> for HashMap<String, JsonValue>

Try to convert the JsonValue value into HashMap<String, JsonValue>. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;
use std::collections::HashMap;

let mut m = HashMap::new();
m.insert("foo".to_string(), 42.0.into());
let v = JsonValue::from(m);
let r = <HashMap<_, _>>::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(1.0);
let r = <HashMap<_, _>>::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl TryFrom<JsonValue> for String

Try to convert the JsonValue value into String. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let v = JsonValue::from("foo".to_string());
let r = String::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(1.0);
let r = String::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl TryFrom<JsonValue> for Vec<JsonValue>

Try to convert the JsonValue value into Vec<JsonValue>. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let v = JsonValue::from(vec![true.into()]);
let r = <Vec<_>>::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(1.0);
let r = <Vec<_>>::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl TryFrom<JsonValue> for bool

Try to convert the JsonValue value into bool. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let v = JsonValue::from(true);
let r = bool::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(1.0);
let r = bool::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl TryFrom<JsonValue> for f64

Try to convert the JsonValue value into f64. UnexpectedValue error happens when trying to convert an incorrect type value.

use tinyjson::JsonValue;
use std::convert::TryFrom;

let v = JsonValue::from(1.0);
let r = f64::try_from(v);
assert!(r.is_ok());

let v = JsonValue::from(true);
let r = f64::try_from(v);
assert!(r.is_err());

type Error = UnexpectedValue

The type returned in the event of a conversion error.

fn try_from(v: JsonValue) -> Result<Self, UnexpectedValue>

Performs the conversion.

impl StructuralPartialEq for JsonValue