540 lines
25 KiB
Rust
540 lines
25 KiB
Rust
//!
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//! ## Quickstart
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//!
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//! Add `evalexpr` as dependency to your `Cargo.toml`:
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//!
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//! ```toml
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//! [dependencies]
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//! evalexpr = "6"
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//! ```
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//!
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//! Then you can use `evalexpr` to **evaluate expressions** like this:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! assert_eq!(eval("1 + 2 + 3"), Ok(Value::from(6)));
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//! // `eval` returns a variant of the `Value` enum,
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//! // while `eval_[type]` returns the respective type directly.
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//! // Both can be used interchangeably.
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//! assert_eq!(eval_int("1 + 2 + 3"), Ok(6));
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//! assert_eq!(eval("1 - 2 * 3"), Ok(Value::from(-5)));
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//! assert_eq!(eval("1.0 + 2 * 3"), Ok(Value::from(7.0)));
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//! assert_eq!(eval("true && 4 > 2"), Ok(Value::from(true)));
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//! ```
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//!
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//! You can **chain** expressions and **assign** to variables like this:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let mut context = HashMapContext::new();
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//! // Assign 5 to a like this
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//! assert_eq!(eval_empty_with_context_mut("a = 5", &mut context), Ok(EMPTY_VALUE));
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//! // The HashMapContext is type safe, so this will fail now
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//! assert_eq!(eval_empty_with_context_mut("a = 5.0", &mut context),
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//! Err(EvalexprError::expected_int(Value::from(5.0))));
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//! // We can check which value the context stores for a like this
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//! assert_eq!(context.get_value("a"), Some(&Value::from(5)));
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//! // And use the value in another expression like this
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//! assert_eq!(eval_int_with_context_mut("a = a + 2; a", &mut context), Ok(7));
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//! // It is also possible to save a bit of typing by using an operator-assignment operator
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//! assert_eq!(eval_int_with_context_mut("a += 2; a", &mut context), Ok(9));
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//! ```
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//!
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//! And you can use **variables** and **functions** in expressions like this:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let context = context_map! {
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//! "five" => 5,
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//! "twelve" => 12,
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//! "f" => Function::new(|argument| {
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//! if let Ok(int) = argument.as_int() {
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//! Ok(Value::Int(int / 2))
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//! } else if let Ok(float) = argument.as_float() {
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//! Ok(Value::Float(float / 2.0))
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//! } else {
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//! Err(EvalexprError::expected_number(argument.clone()))
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//! }
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//! }),
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//! "avg" => Function::new(|argument| {
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//! let arguments = argument.as_tuple()?;
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//!
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//! if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
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//! Ok(Value::Int((a + b) / 2))
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//! } else {
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//! Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
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//! }
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//! })
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//! }.unwrap(); // Do proper error handling here
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//!
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//! assert_eq!(eval_with_context("five + 8 > f(twelve)", &context), Ok(Value::from(true)));
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//! // `eval_with_context` returns a variant of the `Value` enum,
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//! // while `eval_[type]_with_context` returns the respective type directly.
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//! // Both can be used interchangeably.
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//! assert_eq!(eval_boolean_with_context("five + 8 > f(twelve)", &context), Ok(true));
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//! assert_eq!(eval_with_context("avg(2, 4) == 3", &context), Ok(Value::from(true)));
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//! ```
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//!
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//! You can also **precompile** expressions like this:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let precompiled = build_operator_tree("a * b - c > 5").unwrap(); // Do proper error handling here
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//!
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//! let mut context = context_map! {
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//! "a" => 6,
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//! "b" => 2,
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//! "c" => 3
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//! }.unwrap(); // Do proper error handling here
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//! assert_eq!(precompiled.eval_with_context(&context), Ok(Value::from(true)));
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//!
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//! context.set_value("c".into(), 8.into()).unwrap(); // Do proper error handling here
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//! assert_eq!(precompiled.eval_with_context(&context), Ok(Value::from(false)));
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//! // `Node::eval_with_context` returns a variant of the `Value` enum,
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//! // while `Node::eval_[type]_with_context` returns the respective type directly.
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//! // Both can be used interchangeably.
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//! assert_eq!(precompiled.eval_boolean_with_context(&context), Ok(false));
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//! ```
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//!
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//! ## Features
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//!
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//! ### Operators
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//!
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//! This crate offers a set of binary and unary operators for building expressions.
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//! Operators have a precedence to determine their order of evaluation, where operators of higher precedence are evaluated first.
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//! The precedence should resemble that of most common programming languages, especially Rust.
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//! Variables and values have a precedence of 200, and function literals have 190.
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//!
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//! Supported binary operators:
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//!
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//! | Operator | Precedence | Description |
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//! |----------|------------|-------------|
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//! | ^ | 120 | Exponentiation |
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//! | * | 100 | Product |
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//! | / | 100 | Division |
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//! | % | 100 | Modulo |
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//! | + | 95 | Sum or String Concatenation |
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//! | - | 95 | Difference |
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//! | < | 80 | Lower than |
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//! | \> | 80 | Greater than |
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//! | <= | 80 | Lower than or equal |
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//! | \>= | 80 | Greater than or equal |
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//! | == | 80 | Equal |
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//! | != | 80 | Not equal |
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//! | && | 75 | Logical and |
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//! | || | 70 | Logical or |
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//! | = | 50 | Assignment |
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//! | += | 50 | Sum-Assignment or String-Concatenation-Assignment |
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//! | -= | 50 | Difference-Assignment |
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//! | *= | 50 | Product-Assignment |
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//! | /= | 50 | Division-Assignment |
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//! | %= | 50 | Modulo-Assignment |
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//! | ^= | 50 | Exponentiation-Assignment |
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//! | &&= | 50 | Logical-And-Assignment |
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//! | ||= | 50 | Logical-Or-Assignment |
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//! | , | 40 | Aggregation |
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//! | ; | 0 | Expression Chaining |
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//!
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//! Supported unary operators:
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//!
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//! | Operator | Precedence | Description |
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//! |----------|------------|-------------|
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//! | - | 110 | Negation |
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//! | ! | 110 | Logical not |
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//!
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//! Operators that take numbers as arguments can either take integers or floating point numbers.
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//! If one of the arguments is a floating point number, all others are converted to floating point numbers as well, and the resulting value is a floating point number as well.
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//! Otherwise, the result is an integer.
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//! An exception to this is the exponentiation operator that always returns a floating point number.
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//!
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//! #### The Aggregation Operator
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//!
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//! The aggregation operator aggregates a set of values into a tuple.
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//! A tuple can contain arbitrary values, it is not restricted to a single type.
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//! The operator is n-ary, so it supports creating tuples longer than length two.
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//! Example:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! assert_eq!(eval("1, \"b\", 3"),
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//! Ok(Value::from(vec![Value::from(1), Value::from("b"), Value::from(3)])));
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//! ```
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//!
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//! To create nested tuples, use parentheses:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! assert_eq!(eval("1, 2, (true, \"b\")"), Ok(Value::from(vec![
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//! Value::from(1),
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//! Value::from(2),
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//! Value::from(vec![
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//! Value::from(true),
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//! Value::from("b")
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//! ])
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//! ])));
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//! ```
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//!
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//! #### The Assignment Operator
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//!
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//! This crate features the assignment operator, that allows expressions to store their result in a variable in the expression context.
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//! If an expression uses the assignment operator, it must be evaluated with a mutable context.
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//!
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//! Note that assignments are type safe when using the `HashMapContext`.
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//! That means that if an identifier is assigned a value of a type once, it cannot be assigned a value of another type.
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let mut context = HashMapContext::new();
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//! assert_eq!(eval_with_context("a = 5", &context), Err(EvalexprError::ContextNotMutable));
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//! assert_eq!(eval_empty_with_context_mut("a = 5", &mut context), Ok(EMPTY_VALUE));
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//! assert_eq!(eval_empty_with_context_mut("a = 5.0", &mut context),
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//! Err(EvalexprError::expected_int(5.0.into())));
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//! assert_eq!(eval_int_with_context("a", &context), Ok(5));
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//! assert_eq!(context.get_value("a"), Some(5.into()).as_ref());
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//! ```
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//!
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//! For each binary operator, there exists an equivalent operator-assignment operator.
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//! Here are some examples:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! assert_eq!(eval_int("a = 2; a *= 2; a += 2; a"), Ok(6));
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//! assert_eq!(eval_float("a = 2.2; a /= 2.0 / 4 + 1; a"), Ok(2.2 / (2.0 / 4.0 + 1.0)));
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//! assert_eq!(eval_string("a = \"abc\"; a += \"def\"; a"), Ok("abcdef".to_string()));
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//! assert_eq!(eval_boolean("a = true; a &&= false; a"), Ok(false));
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//! ```
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//!
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//! #### The Expression Chaining Operator
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//!
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//! The expression chaining operator works as one would expect from programming languages that use the semicolon to end statements, like `Rust`, `C` or `Java`.
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//! It has the special feature that it returns the value of the last expression in the expression chain.
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//! If the last expression is terminated by a semicolon as well, then `Value::Empty` is returned.
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//! Expression chaining is useful together with assignment to create small scripts.
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let mut context = HashMapContext::new();
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//! assert_eq!(eval("1;2;3;4;"), Ok(Value::Empty));
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//! assert_eq!(eval("1;2;3;4"), Ok(4.into()));
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//!
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//! // Initialization of variables via script
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//! assert_eq!(eval_empty_with_context_mut("hp = 1; max_hp = 5; heal_amount = 3;", &mut context),
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//! Ok(EMPTY_VALUE));
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//! // Precompile healing script
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//! let healing_script = build_operator_tree("hp = min(hp + heal_amount, max_hp); hp").unwrap(); // Do proper error handling here
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//! // Execute precompiled healing script
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//! assert_eq!(healing_script.eval_int_with_context_mut(&mut context), Ok(4));
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//! assert_eq!(healing_script.eval_int_with_context_mut(&mut context), Ok(5));
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//! ```
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//!
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//! ### Contexts
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//!
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//! An expression evaluator that just evaluates expressions would be useful already, but this crate can do more.
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//! It allows using [*variables*](#variables), [*assignments*](#the-assignment-operator), [*statement chaining*](#the-expression-chaining-operator) and [*user-defined functions*](#user-defined-functions) within an expression.
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//! When assigning to variables, the assignment is stored in a context.
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//! When the variable is read later on, it is read from the context.
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//! Contexts can be preserved between multiple calls to eval by creating them yourself.
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//! Here is a simple example to show the difference between preserving and not preserving context between evaluations:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! assert_eq!(eval("a = 5;"), Ok(Value::from(())));
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//! // The context is not preserved between eval calls
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//! assert_eq!(eval("a"), Err(EvalexprError::VariableIdentifierNotFound("a".to_string())));
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//!
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//! let mut context = HashMapContext::new();
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//! assert_eq!(eval_with_context_mut("a = 5;", &mut context), Ok(Value::from(())));
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//! // Assignments require mutable contexts
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//! assert_eq!(eval_with_context("a = 6", &context), Err(EvalexprError::ContextNotMutable));
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//! // The HashMapContext is type safe
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//! assert_eq!(eval_with_context_mut("a = 5.5", &mut context),
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//! Err(EvalexprError::ExpectedInt { actual: Value::from(5.5) }));
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//! // Reading a variable does not require a mutable context
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//! assert_eq!(eval_with_context("a", &context), Ok(Value::from(5)));
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//!
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//! ```
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//!
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//! Note that the assignment is forgotten between the two calls to eval in the first example.
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//! In the second part, the assignment is correctly preserved.
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//! Note as well that to assign to a variable, the context needs to be passed as a mutable reference.
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//! When passed as an immutable reference, an error is returned.
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//!
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//! Also, the `HashMapContext` is type safe.
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//! This means that assigning to `a` again with a different type yields an error.
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//! Type unsafe contexts may be implemented if requested.
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//! For reading `a`, it is enough to pass an immutable reference.
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//!
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//! Contexts can also be manipulated in code.
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//! Take a look at the following example:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let mut context = HashMapContext::new();
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//! // We can set variables in code like this...
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//! context.set_value("a".into(), 5.into());
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//! // ...and read from them in expressions
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//! assert_eq!(eval_int_with_context("a", &context), Ok(5));
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//! // We can write or overwrite variables in expressions...
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//! assert_eq!(eval_with_context_mut("a = 10; b = 1.0;", &mut context), Ok(().into()));
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//! // ...and read the value in code like this
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//! assert_eq!(context.get_value("a"), Some(&Value::from(10)));
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//! assert_eq!(context.get_value("b"), Some(&Value::from(1.0)));
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//! ```
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//!
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//! Contexts are also required for user-defined functions.
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//! Those can be passed one by one with the `set_function` method, but it might be more convenient to use the `context_map!` macro instead:
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//!
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//! ```rust
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//! use evalexpr::*;
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//!
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//! let context = context_map!{
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//! "f" => Function::new(|args| Ok(Value::from(args.as_int()? + 5))),
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//! }.unwrap_or_else(|error| panic!("Error creating context: {}", error));
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//! assert_eq!(eval_int_with_context("f 5", &context), Ok(10));
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//! ```
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//!
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//! For more information about user-defined functions, refer to the respective [section](#user-defined-functions).
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//!
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//! ### Builtin Functions
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//!
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//! This crate offers a set of builtin functions.
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//!
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//! | Identifier | Argument Amount | Argument Types | Description |
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//! |----------------------|-----------------|------------------------|-------------|
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//! | `min` | >= 1 | Numeric | Returns the minimum of the arguments |
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//! | `max` | >= 1 | Numeric | Returns the maximum of the arguments |
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//! | `len` | 1 | String/Tuple | Returns the character length of a string, or the amount of elements in a tuple (not recursively) |
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//! | `floor` | 1 | Numeric | Returns the largest integer less than or equal to a number |
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//! | `round` | 1 | Numeric | Returns the nearest integer to a number. Rounds half-way cases away from 0.0 |
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//! | `ceil` | 1 | Numeric | Returns the smallest integer greater than or equal to a number |
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//! | `math::ln` | 1 | Numeric | Returns the natural logarithm of the number |
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//! | `math::log` | 2 | Numeric, Numeric | Returns the logarithm of the number with respect to an arbitrary base |
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//! | `math::log2` | 1 | Numeric | Returns the base 2 logarithm of the number |
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//! | `math::log10` | 1 | Numeric | Returns the base 10 logarithm of the number |
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//! | `math::exp` | 1 | Numeric | Returns `e^(number)`, (the exponential function) |
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//! | `math::exp2` | 1 | Numeric | Returns `2^(number)` |
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//! | `math::pow` | 2 | Numeric, Numeric | Raises a number to the power of the other number |
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//! | `math::cos` | 1 | Numeric | Computes the cosine of a number (in radians) |
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//! | `math::acos` | 1 | Numeric | Computes the arccosine of a number. The return value is in radians in the range [0, pi] or NaN if the number is outside the range [-1, 1] |
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//! | `math::cosh` | 1 | Numeric | Hyperbolic cosine function |
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//! | `math::acosh` | 1 | Numeric | Inverse hyperbolic cosine function |
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//! | `math::sin` | 1 | Numeric | Computes the sine of a number (in radians) |
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//! | `math::asin` | 1 | Numeric | Computes the arcsine of a number. The return value is in radians in the range [-pi/2, pi/2] or NaN if the number is outside the range [-1, 1] |
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//! | `math::sinh` | 1 | Numeric | Hyperbolic sine function |
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//! | `math::asinh` | 1 | Numeric | Inverse hyperbolic sine function |
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//! | `math::tan` | 1 | Numeric | Computes the tangent of a number (in radians) |
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//! | `math::atan` | 1 | Numeric | Computes the arctangent of a number. The return value is in radians in the range [-pi/2, pi/2] |
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//! | `math::atan2` | 2 | Numeric, Numeric | Computes the four quadrant arctangent in radians |
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//! | `math::tanh` | 1 | Numeric | Hyperbolic tangent function |
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//! | `math::atanh` | 1 | Numeric | Inverse hyperbolic tangent function. |
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//! | `math::sqrt` | 1 | Numeric | Returns the square root of a number. Returns NaN for a negative number |
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//! | `math::cbrt` | 1 | Numeric | Returns the cube root of a number |
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//! | `math::hypot` | 2 | Numeric | Calculates the length of the hypotenuse of a right-angle triangle given legs of length given by the two arguments |
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//! | `str::regex_matches` | 2 | String, String | Returns true if the first argument matches the regex in the second argument (Requires `regex_support` feature flag) |
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//! | `str::regex_replace` | 3 | String, String, String | Returns the first argument with all matches of the regex in the second argument replaced by the third argument (Requires `regex_support` feature flag) |
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//! | `str::to_lowercase` | 1 | String | Returns the lower-case version of the string |
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//! | `str::to_uppercase` | 1 | String | Returns the upper-case version of the string |
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//! | `str::trim` | 1 | String | Strips whitespace from the start and the end of the string |
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//! | `str::from` | >= 0 | Any | Returns passed value as string |
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//!
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//! The `min` and `max` functions can deal with a mixture of integer and floating point arguments.
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//! If the maximum or minimum is an integer, then an integer is returned.
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//! Otherwise, a float is returned.
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//!
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//! The regex functions require the feature flag `regex_support`.
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//!
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//! ### Values
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//!
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//! Operators take values as arguments and produce values as results.
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//! Values can be booleans, integer or floating point numbers, strings, tuples or the empty type.
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//! Values are denoted as displayed in the following table.
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//!
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//! | Value type | Example |
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//! |------------|---------|
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//! | `Value::String` | `"abc"`, `""`, `"a\"b\\c"` |
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//! | `Value::Boolean` | `true`, `false` |
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//! | `Value::Int` | `3`, `-9`, `0`, `135412` |
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//! | `Value::Float` | `3.`, `.35`, `1.00`, `0.5`, `123.554` |
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//! | `Value::Tuple` | `(3, 55.0, false, ())`, `(1, 2)` |
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//! | `Value::Empty` | `()` |
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//!
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//! Integers are internally represented as `i64`, and floating point numbers are represented as `f64`.
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//! Tuples are represented as `Vec<Value>` and empty values are not stored, but represented by Rust's unit type `()` where necessary.
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//!
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//! There exist type aliases for some of the types.
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//! They include `IntType`, `FloatType`, `TupleType` and `EmptyType`.
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//!
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//! Values can be constructed either directly or using the `From` trait.
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//! They can be decomposed using the `Value::as_[type]` methods.
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//! The type of a value can be checked using the `Value::is_[type]` methods.
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//!
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//! **Examples for constructing a value:**
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//!
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//! | Code | Result |
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//! |------|--------|
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//! | `Value::from(4)` | `Value::Int(4)` |
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//! | `Value::from(4.4)` | `Value::Float(4.4)` |
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//! | `Value::from(true)` | `Value::Boolean(true)` |
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//! | `Value::from(vec![Value::from(3)])` | `Value::Tuple(vec![Value::Int(3)])` |
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//!
|
|
//! **Examples for deconstructing a value:**
|
|
//!
|
|
//! | Code | Result |
|
|
//! |------|--------|
|
|
//! | `Value::from(4).as_int()` | `Ok(4)` |
|
|
//! | `Value::from(4.4).as_float()` | `Ok(4.4)` |
|
|
//! | `Value::from(true).as_int()` | `Err(Error::ExpectedInt {actual: Value::Boolean(true)})` |
|
|
//!
|
|
//! Values have a precedence of 200.
|
|
//!
|
|
//! ### Variables
|
|
//!
|
|
//! This crate allows to compile parameterizable formulas by using variables.
|
|
//! A variable is a literal in the formula, that does not contain whitespace or can be parsed as value.
|
|
//! For working with variables, a [context](#contexts) is required.
|
|
//! It stores the mappings from variables to their values.
|
|
//!
|
|
//! Variables do not have fixed types in the expression itself, but are typed by the context.
|
|
//! Once a variable is assigned a value of a specific type, it cannot be assigned a value of another type.
|
|
//! This might change in the future and can be changed by using a type-unsafe context (not provided by this crate as of now).
|
|
//!
|
|
//! Here are some examples and counter-examples on expressions that are interpreted as variables:
|
|
//!
|
|
//! | Expression | Variable? | Explanation |
|
|
//! |------------|--------|-------------|
|
|
//! | `a` | yes | |
|
|
//! | `abc` | yes | |
|
|
//! | `a<b` | no | Expression is interpreted as variable `a`, operator `<` and variable `b` |
|
|
//! | `a b` | no | Expression is interpreted as function `a` applied to argument `b` |
|
|
//! | `123` | no | Expression is interpreted as `Value::Int` |
|
|
//! | `true` | no | Expression is interpreted as `Value::Bool` |
|
|
//! | `.34` | no | Expression is interpreted as `Value::Float` |
|
|
//!
|
|
//! Variables have a precedence of 200.
|
|
//!
|
|
//! ### User-Defined Functions
|
|
//!
|
|
//! This crate allows to define arbitrary functions to be used in parsed expressions.
|
|
//! A function is defined as a `Function` instance, wrapping an `fn(&Value) -> EvalexprResult<Value>`.
|
|
//! The definition needs to be included in the [`Context`](#contexts) that is used for evaluation.
|
|
//! As of now, functions cannot be defined within the expression, but that might change in the future.
|
|
//!
|
|
//! The function gets passed what ever value is directly behind it, be it a tuple or a single values.
|
|
//! If there is no value behind a function, it is interpreted as a variable instead.
|
|
//! More specifically, a function needs to be followed by either an opening brace `(`, another literal, or a value.
|
|
//! While not including special support for multi-valued functions, they can be realized by requiring a single tuple argument.
|
|
//!
|
|
//! Be aware that functions need to verify the types of values that are passed to them.
|
|
//! The `error` module contains some shortcuts for verification, and error types for passing a wrong value type.
|
|
//! Also, most numeric functions need to distinguish between being called with integers or floating point numbers, and act accordingly.
|
|
//!
|
|
//! Here are some examples and counter-examples on expressions that are interpreted as function calls:
|
|
//!
|
|
//! | Expression | Function? | Explanation |
|
|
//! |------------|--------|-------------|
|
|
//! | `a v` | yes | |
|
|
//! | `x 5.5` | yes | |
|
|
//! | `a (3, true)` | yes | |
|
|
//! | `a b 4` | yes | Call `a` with the result of calling `b` with `4` |
|
|
//! | `5 b` | no | Error, value cannot be followed by a literal |
|
|
//! | `12 3` | no | Error, value cannot be followed by a value |
|
|
//! | `a 5 6` | no | Error, function call cannot be followed by a value |
|
|
//!
|
|
//! Functions have a precedence of 190.
|
|
//!
|
|
//! ### [Serde](https://serde.rs)
|
|
//!
|
|
//! To use this crate with serde, the `serde_support` feature flag has to be set.
|
|
//! This can be done like this in the `Cargo.toml`:
|
|
//!
|
|
//! ```toml
|
|
//! [dependencies]
|
|
//! evalexpr = {version = "6", features = ["serde_support"]}
|
|
//! ```
|
|
//!
|
|
//! This crate implements `serde::de::Deserialize` for its type `Node` that represents a parsed expression tree.
|
|
//! The implementation expects a [serde `string`](https://serde.rs/data-model.html) as input.
|
|
//! Example parsing with [ron format](docs.rs/ron):
|
|
//!
|
|
//! ```rust
|
|
//! # #[cfg(feature = "serde_support")] {
|
|
//! extern crate ron;
|
|
//! use evalexpr::*;
|
|
//!
|
|
//! let mut context = context_map!{
|
|
//! "five" => 5
|
|
//! }.unwrap(); // Do proper error handling here
|
|
//!
|
|
//! // In ron format, strings are surrounded by "
|
|
//! let serialized_free = "\"five * five\"";
|
|
//! match ron::de::from_str::<Node>(serialized_free) {
|
|
//! Ok(free) => assert_eq!(free.eval_with_context(&context), Ok(Value::from(25))),
|
|
//! Err(error) => {
|
|
//! () // Handle error
|
|
//! }
|
|
//! }
|
|
//! # }
|
|
//! ```
|
|
//!
|
|
//! With `serde`, expressions can be integrated into arbitrarily complex data.
|
|
//!
|
|
//! The crate also implements `Serialize` and `Deserialize` for the `HashMapContext`,
|
|
//! but note that only the variables get (de)serialized, not the functions.
|
|
//!
|
|
//! ## License
|
|
//!
|
|
//! This crate is primarily distributed under the terms of the MIT license.
|
|
//! See [LICENSE](LICENSE) for details.
|
|
//!
|
|
|
|
#![deny(missing_docs)]
|
|
#![forbid(unsafe_code)]
|
|
|
|
#[cfg(feature = "regex_support")]
|
|
extern crate regex;
|
|
#[cfg(test)]
|
|
extern crate ron;
|
|
#[cfg(feature = "serde_support")]
|
|
extern crate serde;
|
|
#[cfg(feature = "serde_support")]
|
|
#[macro_use]
|
|
extern crate serde_derive;
|
|
|
|
pub use crate::{
|
|
context::{
|
|
Context, ContextWithMutableFunctions, ContextWithMutableVariables, EmptyContext,
|
|
HashMapContext,
|
|
},
|
|
error::{EvalexprError, EvalexprResult},
|
|
function::Function,
|
|
interface::*,
|
|
operator::Operator,
|
|
token::PartialToken,
|
|
tree::Node,
|
|
value::{value_type::ValueType, EmptyType, FloatType, IntType, TupleType, Value, EMPTY_VALUE},
|
|
};
|
|
|
|
mod context;
|
|
pub mod error;
|
|
#[cfg(feature = "serde_support")]
|
|
mod feature_serde;
|
|
mod function;
|
|
mod interface;
|
|
mod operator;
|
|
mod token;
|
|
mod tree;
|
|
mod value;
|
|
|
|
// Exports
|