1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161
use crate::evaluator::{Function, Evaluator, SyntaxError, Context}; use crate::evaluator::ast::SyntaxNode; /// A wrapper for a `Fn(&[String]) -> String`, to be used in [Evaluator]. /// /// /// Example: /// ``` /// use rubble_templates::evaluator::{Evaluator, Function, SyntaxError}; /// use rubble_templates::evaluator::ast::SyntaxNode; /// use std::collections::HashMap; /// use rubble_templates::template::Template; /// use rubble_templates::compile_template_from_string; /// use rubble_templates::evaluator::functions::SimpleFunction; /// /// fn plus_function(parameters: &[String]) -> String { /// parameters.iter() /// .map(|param| /// param.parse::<i32>().unwrap() /// ) /// .sum::<i32>() /// .to_string() /// } /// /// let mut functions: HashMap<String, Box<dyn Function>> = HashMap::new(); /// functions.insert("plus".to_string(), SimpleFunction::new(plus_function)); // will be treated as Box<dyn Function> /// /// let variables: HashMap<String, String> = HashMap::new(); /// /// let result = compile_template_from_string("2 + 2 = {{ plus 2 2 }}".to_string(), variables, functions); /// assert_eq!(result.ok(), Some("2 + 2 = 4".to_string())); /// ``` pub struct SimpleFunction<F> where F: Fn(&[String]) -> String { function: F } impl<F> SimpleFunction<F> where F: Fn(&[String]) -> String { pub fn new(function: F) -> Box<SimpleFunction<F>> { Box::new(SimpleFunction { function }) } } impl<F> Function for SimpleFunction<F> where F: Fn(&[String]) -> String { fn evaluate(&self, evaluator: &dyn Evaluator, parameters: &[SyntaxNode], context: &mut Context) -> Result<String, SyntaxError> { let parameters = resolve_params(evaluator, parameters, context); match parameters { Ok(parameters) => Ok((self.function)(¶meters)), Err(err) => Err(err) } } } /// A wrapper for a `Fn(&dyn Evaluator, &[String], &HashMap<String, String>) -> Result<String, SyntaxError>`, to be used in [Evaluator]. /// /// Example: /// ``` /// use rubble_templates::evaluator::{Evaluator, Function, SyntaxError, Context}; /// use rubble_templates::evaluator::ast::SyntaxNode; /// use std::collections::HashMap; /// use rubble_templates::template::Template; /// use rubble_templates::compile_template_from_string; /// use rubble_templates::evaluator::functions::FunctionWithContext; /// /// fn plus_function(parameters: &[String], _context: &mut Context) -> Result<String, SyntaxError> { /// Ok( /// parameters.iter() /// .map(|param| /// param.parse::<i32>().unwrap() /// ) /// .sum::<i32>() /// .to_string() /// ) /// } /// /// let mut functions: HashMap<String, Box<dyn Function>> = HashMap::new(); /// functions.insert("plus".to_string(), FunctionWithContext::new(plus_function)); // will be treated as Box<dyn Function> /// /// let variables: HashMap<String, String> = HashMap::new(); /// /// let result = compile_template_from_string("2 + 2 = {{ plus 2 2 }}".to_string(), variables, functions); /// assert_eq!(result.ok(), Some("2 + 2 = 4".to_string())); /// ``` pub struct FunctionWithContext<F> where F: Fn(&[String], &mut Context) -> Result<String, SyntaxError> { function: F } impl<F> FunctionWithContext<F> where F: Fn(&[String], &mut Context) -> Result<String, SyntaxError> { pub fn new(function: F) -> Box<FunctionWithContext<F>> { Box::new(FunctionWithContext { function }) } } impl<F> Function for FunctionWithContext<F> where F: Fn(&[String], &mut Context) -> Result<String, SyntaxError> { fn evaluate(&self, evaluator: &dyn Evaluator, parameters: &[SyntaxNode], context: &mut Context) -> Result<String, SyntaxError> { let parameters = resolve_params(evaluator, parameters, context); match parameters { Ok(parameters) => (self.function)(¶meters, context), Err(err) => Err(err) } } } /// A wrapper for a `Fn(&dyn Evaluator, &[SyntaxNode], &HashMap<String, String>) -> Result<String, SyntaxError>`, to be used in [Evaluator]. /// /// Example: /// ``` /// use rubble_templates::evaluator::{Evaluator, Function, SyntaxError, Context}; /// use rubble_templates::evaluator::ast::SyntaxNode; /// use std::collections::HashMap; /// use rubble_templates::template::Template; /// use rubble_templates::compile_template_from_string; /// use rubble_templates::evaluator::functions::FunctionWithAst; /// /// fn plus_function(evaluator: &dyn Evaluator, parameters: &[SyntaxNode], context: &mut Context) -> Result<String, SyntaxError> { /// Ok( /// parameters.iter() /// .map(|node| /// evaluator.evaluate(node, context).unwrap().parse::<i32>().unwrap() /// ) /// .sum::<i32>() /// .to_string() /// ) /// } /// /// let mut functions: HashMap<String, Box<dyn Function>> = HashMap::new(); /// functions.insert("plus".to_string(), FunctionWithAst::new(plus_function)); // will be treated as Box<dyn Function> /// /// let variables: HashMap<String, String> = HashMap::new(); /// /// let result = compile_template_from_string("2 + 2 = {{ plus 2 2 }}".to_string(), variables, functions); /// assert_eq!(result.ok(), Some("2 + 2 = 4".to_string())); /// ``` pub struct FunctionWithAst<F> where F: Fn(&dyn Evaluator, &[SyntaxNode], &mut Context) -> Result<String, SyntaxError> { function: F } impl<F> FunctionWithAst<F> where F: Fn(&dyn Evaluator, &[SyntaxNode], &mut Context) -> Result<String, SyntaxError> { pub fn new(function: F) -> Box<FunctionWithAst<F>> { Box::new(FunctionWithAst { function }) } } impl<F> Function for FunctionWithAst<F> where F: Fn(&dyn Evaluator, &[SyntaxNode], &mut Context) -> Result<String, SyntaxError> { fn evaluate(&self, evaluator: &dyn Evaluator, parameters: &[SyntaxNode], context: &mut Context) -> Result<String, SyntaxError> { (self.function)(evaluator, ¶meters, context) } } /// Resolves a slice of [SyntaxNode]s to a `Vec` of strings. /// /// Invokes Evaluator on each [SyntaxNode] and returns a `Result` containing a `Vec` of strings (baked parameters ready to use) /// or a [SyntaxError] if any parameter evaluation fails. pub fn resolve_params(evaluator: &dyn Evaluator, parameters: &[SyntaxNode], context: &mut Context) -> Result<Vec<String>, SyntaxError> { parameters.iter() .map(|parameter| { evaluator.evaluate(parameter, context) }) .collect::<Result<Vec<String>, SyntaxError>>() }