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Prepare for 6.0.0.

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This commit is contained in:
Sebastian Schmidt 2021-05-28 15:14:52 +03:00
parent 60c86863a6
commit b4974a8a2b
2 changed files with 10 additions and 22 deletions
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24
README.md
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@ -18,13 +18,7 @@ Add `evalexpr` as dependency to your `Cargo.toml`:
```toml ```toml
[dependencies] [dependencies]
evalexpr = "5" evalexpr = "6"
```
Add the `extern crate` definition to your `main.rs` or `lib.rs`:
```rust
extern crate evalexpr;
``` ```
Then you can use `evalexpr` to **evaluate expressions** like this: Then you can use `evalexpr` to **evaluate expressions** like this:
@ -69,7 +63,7 @@ use evalexpr::*;
let context = context_map! { let context = context_map! {
"five" => 5, "five" => 5,
"twelve" => 12, "twelve" => 12,
"f" => Function::new(Box::new(|argument| { "f" => Function::new(|argument| {
if let Ok(int) = argument.as_int() { if let Ok(int) = argument.as_int() {
Ok(Value::Int(int / 2)) Ok(Value::Int(int / 2))
} else if let Ok(float) = argument.as_float() { } else if let Ok(float) = argument.as_float() {
@ -77,8 +71,8 @@ let context = context_map! {
} else { } else {
Err(EvalexprError::expected_number(argument.clone())) Err(EvalexprError::expected_number(argument.clone()))
} }
})), }),
"avg" => Function::new(Box::new(|argument| { "avg" => Function::new(|argument| {
let arguments = argument.as_tuple()?; let arguments = argument.as_tuple()?;
if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) { if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
@ -86,7 +80,7 @@ let context = context_map! {
} else { } else {
Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0)) Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
} }
})) })
}.unwrap(); // Do proper error handling here }.unwrap(); // Do proper error handling here
assert_eq!(eval_with_context("five + 8 > f(twelve)", &context), Ok(Value::from(true))); assert_eq!(eval_with_context("five + 8 > f(twelve)", &context), Ok(Value::from(true)));
@ -209,7 +203,7 @@ Note that assignments are type safe, meaning if an identifier is assigned a valu
use evalexpr::*; use evalexpr::*;
let mut context = HashMapContext::new(); let mut context = HashMapContext::new();
assert_eq!(eval_with_context("a = 5", &context), Err(EvalexprError::ContextNotManipulable)); assert_eq!(eval_with_context("a = 5", &context), Err(EvalexprError::ContextNotMutable));
assert_eq!(eval_empty_with_context_mut("a = 5", &mut context), Ok(EMPTY_VALUE)); assert_eq!(eval_empty_with_context_mut("a = 5", &mut context), Ok(EMPTY_VALUE));
assert_eq!(eval_empty_with_context_mut("a = 5.0", &mut context), assert_eq!(eval_empty_with_context_mut("a = 5.0", &mut context),
Err(EvalexprError::expected_int(5.0.into()))); Err(EvalexprError::expected_int(5.0.into())));
@ -256,7 +250,7 @@ assert_eq!(healing_script.eval_int_with_context_mut(&mut context), Ok(5));
### Contexts ### Contexts
An expression evaluator that just evaluates expressions would be useful already, but this crate can to more. An expression evaluator that just evaluates expressions would be useful already, but this crate can to more.
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. 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.
When assigning to variables, the assignment is stored in a context. When assigning to variables, the assignment is stored in a context.
When the variable is read later on, it is read from the context. When the variable is read later on, it is read from the context.
Contexts can be preserved between multiple calls to eval by creating them yourself. Contexts can be preserved between multiple calls to eval by creating them yourself.
@ -272,7 +266,7 @@ assert_eq!(eval("a"), Err(EvalexprError::VariableIdentifierNotFound("a".to_strin
let mut context = HashMapContext::new(); let mut context = HashMapContext::new();
assert_eq!(eval_with_context_mut("a = 5;", &mut context), Ok(Value::from(()))); assert_eq!(eval_with_context_mut("a = 5;", &mut context), Ok(Value::from(())));
// Assignments require mutable contexts // Assignments require mutable contexts
assert_eq!(eval_with_context("a = 6", &context), Err(EvalexprError::ContextNotManipulable)); assert_eq!(eval_with_context("a = 6", &context), Err(EvalexprError::ContextNotMutable));
// The HashMapContext is type safe // The HashMapContext is type safe
assert_eq!(eval_with_context_mut("a = 5.5", &mut context), assert_eq!(eval_with_context_mut("a = 5.5", &mut context),
Err(EvalexprError::ExpectedInt { actual: Value::from(5.5) })); Err(EvalexprError::ExpectedInt { actual: Value::from(5.5) }));
@ -315,7 +309,7 @@ Those can be passed one by one with the `set_function` method, but it might be m
use evalexpr::*; use evalexpr::*;
let context = context_map!{ let context = context_map!{
"f" => Function::new(Box::new(|args| Ok(Value::from(args.as_int()? + 5)))), "f" => Function::new(|args| Ok(Value::from(args.as_int()? + 5))),
}.unwrap_or_else(|error| panic!("Error creating context: {}", error)); }.unwrap_or_else(|error| panic!("Error creating context: {}", error));
assert_eq!(eval_int_with_context("f 5", &context), Ok(10)); assert_eq!(eval_int_with_context("f 5", &context), Ok(10));
``` ```

8
src/lib.rs
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@ -5,13 +5,7 @@
//! //!
//! ```toml //! ```toml
//! [dependencies] //! [dependencies]
//! evalexpr = "5" //! evalexpr = "6"
//! ```
//!
//! Add the `extern crate` definition to your `main.rs` or `lib.rs`:
//!
//! ```rust
//! extern crate evalexpr;
//! ``` //! ```
//! //!
//! Then you can use `evalexpr` to **evaluate expressions** like this: //! Then you can use `evalexpr` to **evaluate expressions** like this: