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Merge pull request #49 from lovasoa/master

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Use the new context macro in the README examples
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ISibboI 2019-04-26 17:36:15 +02:00 committed by GitHub
commit b85e8e1b75
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2 changed files with 60 additions and 54 deletions
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57
README.md
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@ -64,28 +64,29 @@ And you can use **variables** and **functions** in expressions like this:
use evalexpr::*;
use evalexpr::error::expect_number;
let mut context = HashMapContext::new();
context.set_value("five".into(), 5.into()).unwrap(); // Do proper error handling here
context.set_value("twelve".into(), 12.into()).unwrap(); // Do proper error handling here
context.set_function("f".into(), Function::new(Some(1) /* argument amount */, Box::new(|arguments| {
if let Value::Int(int) = arguments[0] {
Ok(Value::Int(int / 2))
} else if let Value::Float(float) = arguments[0] {
Ok(Value::Float(float / 2.0))
} else {
Err(EvalexprError::expected_number(arguments[0].clone()))
}
}))).unwrap(); // Do proper error handling here
context.set_function("avg".into(), Function::new(Some(2) /* argument amount */, Box::new(|arguments| {
expect_number(&arguments[0])?;
expect_number(&arguments[1])?;
let context = context_map! {
"five" => 5,
"twelve" => 12,
"f" => Function::new(Some(1) /* argument amount */, Box::new(|arguments| {
if let Value::Int(int) = arguments[0] {
Ok(Value::Int(int / 2))
} else if let Value::Float(float) = arguments[0] {
Ok(Value::Float(float / 2.0))
} else {
Err(EvalexprError::expected_number(arguments[0].clone()))
}
})),
"avg" => Function::new(Some(2) /* argument amount */, Box::new(|arguments| {
expect_number(&arguments[0])?;
expect_number(&arguments[1])?;
if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
Ok(Value::Int((a + b) / 2))
} else {
Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
}
}))).unwrap(); // Do proper error handling here
if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
Ok(Value::Int((a + b) / 2))
} else {
Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
}
}))
}.unwrap(); // Do proper error handling here
assert_eq!(eval_with_context("five + 8 > f(twelve)", &context), Ok(Value::from(true)));
// `eval_with_context` returns a variant of the `Value` enum,
@ -102,10 +103,11 @@ use evalexpr::*;
let precompiled = build_operator_tree("a * b - c > 5").unwrap(); // Do proper error handling here
let mut context = HashMapContext::new();
context.set_value("a".into(), 6.into()).unwrap(); // Do proper error handling here
context.set_value("b".into(), 2.into()).unwrap(); // Do proper error handling here
context.set_value("c".into(), 3.into()).unwrap(); // Do proper error handling here
let mut context = context_map! {
"a" => 6,
"b" => 2,
"c" => 3
}.unwrap(); // Do proper error handling here
assert_eq!(precompiled.eval_with_context(&context), Ok(Value::from(true)));
context.set_value("c".into(), 8.into()).unwrap(); // Do proper error handling here
@ -344,8 +346,9 @@ Example parsing with [ron format](docs.rs/ron):
extern crate ron;
use evalexpr::*;
let mut context = HashMapContext::new();
context.set_value("five".into(), 5.into()).unwrap(); // Do proper error handling here
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\"";

57
src/lib.rs
View File

@ -51,28 +51,29 @@
//! use evalexpr::*;
//! use evalexpr::error::expect_number;
//!
//! let mut context = HashMapContext::new();
//! context.set_value("five".into(), 5.into()).unwrap(); // Do proper error handling here
//! context.set_value("twelve".into(), 12.into()).unwrap(); // Do proper error handling here
//! context.set_function("f".into(), Function::new(Some(1) /* argument amount */, Box::new(|arguments| {
//! if let Value::Int(int) = arguments[0] {
//! Ok(Value::Int(int / 2))
//! } else if let Value::Float(float) = arguments[0] {
//! Ok(Value::Float(float / 2.0))
//! } else {
//! Err(EvalexprError::expected_number(arguments[0].clone()))
//! }
//! }))).unwrap(); // Do proper error handling here
//! context.set_function("avg".into(), Function::new(Some(2) /* argument amount */, Box::new(|arguments| {
//! expect_number(&arguments[0])?;
//! expect_number(&arguments[1])?;
//! let context = context_map! {
//! "five" => 5,
//! "twelve" => 12,
//! "f" => Function::new(Some(1) /* argument amount */, Box::new(|arguments| {
//! if let Value::Int(int) = arguments[0] {
//! Ok(Value::Int(int / 2))
//! } else if let Value::Float(float) = arguments[0] {
//! Ok(Value::Float(float / 2.0))
//! } else {
//! Err(EvalexprError::expected_number(arguments[0].clone()))
//! }
//! })),
//! "avg" => Function::new(Some(2) /* argument amount */, Box::new(|arguments| {
//! expect_number(&arguments[0])?;
//! expect_number(&arguments[1])?;
//!
//! if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
//! Ok(Value::Int((a + b) / 2))
//! } else {
//! Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
//! }
//! }))).unwrap(); // Do proper error handling here
//! if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
//! Ok(Value::Int((a + b) / 2))
//! } else {
//! Ok(Value::Float((arguments[0].as_number()? + arguments[1].as_number()?) / 2.0))
//! }
//! }))
//! }.unwrap(); // Do proper error handling here
//!
//! assert_eq!(eval_with_context("five + 8 > f(twelve)", &context), Ok(Value::from(true)));
//! // `eval_with_context` returns a variant of the `Value` enum,
@ -89,10 +90,11 @@
//!
//! let precompiled = build_operator_tree("a * b - c > 5").unwrap(); // Do proper error handling here
//!
//! let mut context = HashMapContext::new();
//! context.set_value("a".into(), 6.into()).unwrap(); // Do proper error handling here
//! context.set_value("b".into(), 2.into()).unwrap(); // Do proper error handling here
//! context.set_value("c".into(), 3.into()).unwrap(); // Do proper error handling here
//! let mut context = context_map! {
//! "a" => 6,
//! "b" => 2,
//! "c" => 3
//! }.unwrap(); // Do proper error handling here
//! assert_eq!(precompiled.eval_with_context(&context), Ok(Value::from(true)));
//!
//! context.set_value("c".into(), 8.into()).unwrap(); // Do proper error handling here
@ -331,8 +333,9 @@
//! extern crate ron;
//! use evalexpr::*;
//!
//! let mut context = HashMapContext::new();
//! context.set_value("five".into(), 5.into()).unwrap(); // Do proper error handling here
//! 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\"";