proper aliasing for the modules imported with proper malayalam grammar for it

Author: Sreyas-Sreelal

src/executor/ast.rs

@@ -17,7 +17,7 @@ pub enum Statement {
     EmptyExpression((usize, usize), Expression),
     Return((usize, usize), Expression),
     Write((usize, usize), Expression),
-    Import((usize, usize), Vec<usize>),
+    Import((usize, usize), Vec<usize>, Option<usize>),
 }
 
 #[derive(Debug, Clone, PartialEq)]

src/executor/mod.rs

@@ -221,7 +221,7 @@ impl Executor {
                     self.return_storage = self.eval_arithmetic_logic_expression(expr)?;
                     self.subroutine_exit_flag = true;
                 }
-                Statement::Import((p, q), path) => {
+                Statement::Import((p, q), path, alias) => {
                     let mut module_path = String::new();
                     let mut module_name = String::new();
                     for (i, id) in path.iter().enumerate() {
@@ -271,7 +271,11 @@ impl Executor {
                             )),
                         ));
                     }
-                    self.modules.insert(module_name, exec);
+                    let final_name = match alias {
+                        Some(id) => self.get_symbol_name(*id).unwrap(),
+                        None => module_name,
+                    };
+                    self.modules.insert(final_name, exec);
                 }
             }
         }

src/lexer/keywords.rs

@@ -37,7 +37,8 @@ impl Keywords {
             ["um", "ഉം"] => TokenType::Um,
             ["ne_kal", "നെകാൾ"] => TokenType::Nekal,
             ["kodukuga","kodukuka","madakiayakuga","madakiayakuka","കൊടുക്കുക","മടക്കിഅയയ്ക്കുക"] => TokenType::Return,
-            ["ulppeduthuka","ulppeduthuga","ഉൾപ്പെടുത്തുക"] => TokenType::Import
+            ["ulppeduthuka","ulppeduthuga","ഉൾപ്പെടുത്തുക"] => TokenType::Import,
+            ["ennu","ayi","എന്ന്","ആയി"] => TokenType::As
         );
 
         Self { list }

src/lexer/tokens.rs

@@ -41,6 +41,7 @@ pub enum TokenType {
     Import,
     Colon,
     Dot,
+    As,
 }
 
 impl Display for TokenType {
@@ -86,6 +87,7 @@ impl Display for TokenType {
             TokenType::Import => write!(f, "ulppeduthuka"),
             TokenType::Colon => write!(f, ":"),
             TokenType::Dot => write!(f, "."),
+            TokenType::As => write!(f, "ennu"),
         }
     }
 }

src/parser/grammar.lalrpop

@@ -35,7 +35,8 @@ Statement:Statement = {
     <a:@L> <expr:Expression> ";" <b:@R>  => Statement::EmptyExpression((a,b),expr),
     <a:@L> <condition:Conditional> If Loop "{" <s:SourceUnit> "}" <b:@R> => Statement::Loop((a,b),condition,s),
     <a:@L> <condition:ConditionalWithAgglutination> Loop "{" <s:SourceUnit> "}" <b:@R> => Statement::Loop((a,b),condition,s),
-    <a:@L> <path:ImportPath> Import ";" <b:@R> => Statement::Import((a,b), path),
+    <a:@L> <path:ImportPath> <alias:Identifier> As Import ";" <b:@R> => Statement::Import((a,b), path, Some(match alias { TokenType::Symbol(s) => s, _ => unreachable!() })),
+    <a:@L> <path:ImportPath> Import ";" <b:@R> => Statement::Import((a,b), path, None),
 }; 
 
 ImportPath: Vec<usize> = {
@@ -151,6 +152,7 @@ extern {
         "[" => TokenType::SquareOpen,
         "]" => TokenType::SquareClose,        
         Import => TokenType::Import,
+        As => TokenType::As,
         ":" => TokenType::Colon,
         "." => TokenType::Dot,
     }