or/xor

README.md

@@ -44,6 +44,8 @@ Limp has two major constructions. The first is the "atom", which is a singular u
 | `*` | Multiplies all rands given. Requires at least two rands (int/float).
 | `/` | Divides the first rand from the remaining rands. Requires at least two rands (int/float).
 | `and` | Ands all rands given. Requires at least two rands (boolean).
+| `or` | Ors all rands given. Requires at least two rands (boolean).
+| `xor` | Xors all rands given. Requires at least two rands (boolean).
 | `print` | Prints (on new lines) each rand. Requires at least one rand (int/float/boolean).
 | `exit` | Exits the program with a 0 status. With an optional rand, exits with that status  (int/float).
 

src/evaluator.rs

@@ -249,7 +249,7 @@ fn eval_invocation(invocation: Pair<Rule>) -> LimpValue {
 							match rand {
 								Boolean(b) => {
 									if !*b {
-										return Boolean(false)
+										return Boolean(false);
 									}
 								}
 								// TODO: implement bindings
@@ -259,6 +259,47 @@ fn eval_invocation(invocation: Pair<Rule>) -> LimpValue {
 
 						return Boolean(true);
 					},
+					"or" => {
+						if rands.len() < 2 {
+							panic!("Rator `or` expects at least 2 rands!");
+						}
+
+						for rand in rands {
+							match rand {
+								Boolean(b) => {
+									if *b {
+										return Boolean(true);
+									}
+								}
+								// TODO: implement bindings
+								_ => { panic!("Bad type of {:?} for or!", rand)}
+							}
+						}
+
+						return Boolean(false);
+					},
+					"xor" => {
+						if rands.len() < 2 {
+							panic!("Rator `or` expects at least 2 rands!");
+						}
+
+						// Wikipedia: "[xor] may be considered to be an n-ary operator which is true if and only if an odd number of arguments are true"
+						let mut trues = 0;
+
+						for rand in rands {
+							match rand {
+								Boolean(b) => {
+									if *b {
+										trues += 1;
+									}
+								}
+								// TODO: implement bindings
+								_ => { panic!("Bad type of {:?} for or!", rand)}
+							}
+						}
+
+						return Boolean(if trues % 2 == 0 { false } else { true });
+					},
 					"print" => {
 						if rands.len() < 1 {
 							panic!("Rator `print` expects at least 1 rand!");

src/limp.pest

@@ -9,6 +9,6 @@ invocation = { "(" ~ expr_list ~ ")" }
 int = @{ ("+" | "-")? ~ ASCII_DIGIT+ }
 float = @{ ("+" | "-")? ~ ASCII_DIGIT+ ~ "." ~ ASCII_DIGIT+ }
 boolean = { "true" | "false" }
-name = { "+" | "-" | "*" | "/" | "and" | "print" | "exit" }
+name = { "+" | "-" | "*" | "/" | "and" | "or" | "xor" | "print" | "exit" }
 
 WHITESPACE = _{ " " | "\t" | "\n" | "\r" | "\r\n" }