update parser

src/albireo.pest

@@ -17,54 +17,133 @@ keywords   =  {
   | "import"
   | "module"
   | "export"
-}
-identifier = @{ !keywords ~ ASCII_ALPHA ~ ASCII_ALPHANUMERIC* }
-
-function_type_param  = { type }
-function_type_return = { type }
-function_type        = {
-    "fn" ~ function_type_param* ~ "=>" ~ function_type_return
+  | "record"
+  | "tuple"
+  | "type"
+  | "enum"
+  | "auto"
 }
 
-type = {
+// if identifier starts with something like a keyword, it must follows something else
+// in any case, the identifier cannot begin with a digit
+identifier = @{ keywords? ~ ("_" | ASCII_ALPHANUMERIC)+
+                | !keywords ~ ASCII_ALPHA ~ ("_" | ASCII_ALPHANUMERIC)* }
+
+function_type_param  =  { type* }
+function_type_return = _{ type }
+function_type        =  {
+    "fn" ~ function_type_param ~ "=>" ~ function_type_return
+}
+
+// record name { prop: type, prop: type, prop: type }
+record_type_field  =  { identifier ~ ":" ~ type }
+record_type_fields = _{ record_type_field ~ "," ~ record_type_fields | record_type_field }
+record_type        =  {
+    "record" ~ "{" ~ record_type_fields ~ "}"
+}
+
+// tuple (type, type)
+tuple_type_item      = _{ type }
+tuple_type_item_list = _{ tuple_type_item ~ "," ~ tuple_type_item_list | tuple_type_item }
+tuple_type           =  {
+    "tuple" ~ "(" ~ tuple_type_item_list ~ ")"
+}
+
+// enum name { name: type, name: type }
+enum_field  =  { identifier ~ ":" ~ type }
+enum_fields = _{ enum_field ~ "," ~ enum_fields | enum_field }
+enum_type   =  {
+    "enum" ~ "{" ~ enum_fields ~ "}"
+}
+
+// allow for type alias, aka create new type
+type_name        = { identifier }
+type_declaration = { "type" ~ type_name ~ "=" ~ type }
+
+type_number = { "number" }
+type_string = { "string" }
+type_bool   = { "bool" }
+
+// for gradual typing
+type_auto = { "?" | "auto" }
+
+// higher-kinded types will be added later
+// this will be very complex to parse,
+// because allowing types to receive an argument as type
+type = _{
     function_type
-  | "number"
-  | "bool"
-  | "string"
+  | record_type
+  | tuple_type
+  | enum_type
+  | type_name
+  | type_number
+  | type_bool
+  | type_string
 }
 
-number         = @{ ASCII_DIGIT+ }
-string         = @{ "\"" ~ !("\"") ~ ASCII_ALPHANUMERIC* ~ "\"" }
-bool           = @{ "true" | "false" }
-function       =  { "function" ~ function_param* ~ "is" ~ function_body }
-function_param =  { identifier }
-function_body  =  {
-    binding* ~ expr
+number           = @{ ASCII_DIGIT+ }
+string           = @{ "\"" ~ !("\"") ~ ASCII_ALPHANUMERIC* ~ "\"" }
+bool             = @{ "true" | "false" }
+tuple            =  { "tuple" ~ "(" ~ tuple_item_list ~ ")" }
+tuple_item_list  = _{ expr ~ "," ~ tuple_item_list | expr }
+record           =  { "record" ~ "{" ~ record_item_list ~ "}" }
+record_item      =  { identifier ~ ":" ~ expr }
+record_item_list = _{ record_item ~ "," ~ record_item_list | record_item }
+function         =  { "function" ~ function_params ~ "is" ~ function_body }
+function_params  =  { function_param* }
+function_param   = _{ identifier }
+function_body    = _{
+    bindings ~ expr
 }
-binding        =  {
+bindings         =  { binding* }
+binding          =  {
     "let" ~ identifier ~ "=" ~ expr ~ "in"
 }
 
-// will be expr in later version of the language
-if_cond     = { identifier }
-if_branch   = { identifier }
-else_branch = { identifier }
-if_expr     = {
-    // "if" ~ expr ~ "then" ~ expr ~ "else" ~ expr
+if_cond     = _{ expr }
+if_branch   = _{ expr }
+else_branch = _{ expr }
+if_expr     =  {
     "if" ~ if_cond ~ "then" ~ if_branch ~ "else" ~ else_branch
 }
 
-call_function = { identifier }
-call_param    = { identifier | identifier ~ call_param }
-call_expr     = {
-    call_function ~ "(" ~ call_param? ~ ")"
+call_function   = _{ identifier }
+call_param_list = _{ expr ~ ("," ~ expr)* }
+call_param      =  { call_param_list? }
+call_expr       =  {
+    call_function ~ "(" ~ call_param ~ ")"
 }
 
-expr = {
+binop = _{
+    add
+  | sub
+  | div
+  | mul
+  | mod
+  | and
+  | or
+  | xor
+}
+add   =  { "+" }
+sub   =  { "-" }
+div   =  { "/" }
+mul   =  { "*" }
+mod   =  { "%" }
+and   =  { "&" }
+or    =  { "|" }
+xor   =  { "^" }
+// disambiguous between arithmetic and logical operators
+// add comparision
+
+expr        =  {
+  single_expr ~ (binop ~ single_expr)*
+}
+single_expr = _{
     if_expr
   | call_expr
   | identifier
   | value
+  | "(" ~ expr ~ ")"
 }
 
 // function is a value only if we allow to have thunks
@@ -74,17 +153,22 @@ value = _{
     number
   | string
   | bool
+  | tuple
+  | record
   | function
 }
 
-declaration = {
+variable_declaration = {
     identifier ~ ":" ~ type ~ "=" ~ expr
 }
+declaration          = _{
+    type_declaration
+  | variable_declaration
+}
 
-module_name   = @{ identifier }
+module_name   = _{ identifier }
 export_list   = _{
-    identifier
-  | identifier ~ "," ~ export_list
+  identifier ~ ("," ~ identifier)*
 }
 module_export =  {
     "export" ~ export_list
@@ -94,24 +178,24 @@ module_export =  {
 // import module only name, name
 // import module as change_name
 import_list        = _{
-    identifier ~ "," ~ import_list
-  | identifier
+    identifier ~ ("," ~ identifier)*
 }
 import_selective   =  { "only" ~ import_list }
 import_change_name =  { "as" ~ module_name }
-import_types       =  {
+import_types       = _{
     import_selective
   | import_change_name
 }
 module_import      =  { "import" ~ module_name ~ import_types? }
 
+module_export_import = { (module_export | module_import)* }
 module_declare = {
-    "module" ~ module_name ~ module_export* ~ module_import*
+    "module" ~ module_name ~ module_export_import
 }
 
 program = {
-    module_declare ~ declaration*
+    SOI ~ module_declare ~ declaration*
 }
 
 WHITESPACE = _{ " " | NEWLINE }
-COMMENT    = _{ ";.*" ~ NEWLINE }
+COMMENT    = _{ ";" ~ (!NEWLINE ~ ANY)* ~ NEWLINE }

src/albireo.rs

@@ -4,30 +4,365 @@ pub struct AlbireoParser;
 
 use pest::iterators::Pair;
 
-struct Module {
+use std::vec::Vec;
+use std::collections::HashMap;
+
+#[derive(Clone, Debug, Eq, PartialEq, Hash)]
+pub struct Identifier {
     name: String,
-    declaration: HashMap<String, Declaration>
 }
 
-struct Declaration {
-    type: Type,
-    definition: Expression,
+#[derive(Clone, Debug)]
+pub struct Module {
+    module: ModuleInformation,
+    declaration: Vec<Declaration>
 }
 
-enum Type {
+#[derive(Clone, Debug)]
+pub struct ModuleInformation {
+    name: Identifier,
+    export: Export,
+    import: Vec<Import>,
+}
+
+#[derive(Clone, Debug)]
+pub enum Export {
+    All,
+    Selective(Vec<Identifier>),
+}
+
+#[derive(Clone, Debug)]
+pub struct Import {
+    from: Identifier,
+    rename: Identifier, // change name, perhaps
+    imported: Vec<Identifier>,
+}
+
+#[derive(Clone, Debug)]
+pub enum Declaration {
+    Type(Identifier, Type),
+    Variable(Identifier, Type, Box<Expression>),
+}
+
+#[derive(Clone, Debug)]
+pub enum Type {
+    Identifier(Identifier),
     Number,
     String,
     Bool,
-    Function(/*inputs*/Vec<Type>, /*output*/Type)
+    Function(/*inputs*/Vec<Type>, /*output*/Box<Type>),
+    Tuple(Vec<Type>),
 }
 
-// limitation as of now, everything must be passed in as identifier
-enum Expression {
-    IfClause(String, String, String),
-    Application(/*function name*/String, /*params*/Vec<String>), // function call
-    Identifier(String),
+#[derive(Clone, Debug)]
+pub enum BinaryOp {
+    Add, Sub, Div, Mul, Mod, And, Or, Xor
+}
+
+impl Into<BinaryOp> for &str {
+    fn into(self) -> BinaryOp {
+        match self {
+            "+" => BinaryOp::Add,
+            "-" => BinaryOp::Sub,
+            "*" => BinaryOp::Mul,
+            "/" => BinaryOp::Div,
+            "%" => BinaryOp::Mod,
+            // "<" => BinaryOp::Lt,
+            // ">" => BinaryOp::Gt,
+            // "<=" => BinaryOp::Le,
+            // ">=" => BinaryOp::Ge,
+            // "==" => BinaryOp::Eq,
+            // "!=" => BinaryOp::Neq,
+            // "|" => BinaryOp::ArithOr,
+            // "&" => BinaryOp::ArithAnd,
+            // "||" => BinaryOp::LogicalOr,
+            // "&&" => BinaryOp::LogicalAnd,
+            // "<<" => BinaryOp::ShiftLeft,
+            // ">>" => BinaryOp::ShiftRight,
+            // "**" => BinaryOp::Power,
+            _ => {
+                unreachable!()
+            }
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+pub enum Expression {
+    IfClause(Box<Expression>, Box<Expression>, Box<Expression>),
+    Application(/*function name*/Identifier, /*params*/Vec<Box<Expression>>), // function call
+    Identifier(Identifier),
     Number(u64),
     String(String),
     Bool(bool),
-    Function(String, Vec<Binding>, Expression),
+    Function(/*params*/Vec<Identifier>, Vec<Binding>, Box<Expression>),
+    Binary(Box<Expression>, BinaryOp, Box<Expression>),
+    Tuple(Vec<Box<Expression>>),
+}
+
+#[derive(Clone, Debug)]
+pub struct Binding {
+    lhs: Identifier,
+    rhs: Box<Expression>,
+}
+
+fn parse_definition(parsed: Pair<Rule>) -> Box<Expression> {
+    parse_expr(parsed)
+}
+
+fn parse_expr(parsed: Pair<Rule>) -> Box<Expression> {
+    use pest::pratt_parser::PrattParser;
+    use pest::pratt_parser::{Assoc, Op};
+    let pratt =
+        PrattParser::new()
+            .op(Op::infix(Rule::r#mod, Assoc::Left))
+            .op(Op::infix(Rule::add, Assoc::Left) | Op::infix(Rule::sub, Assoc::Left))
+            .op(Op::infix(Rule::mul, Assoc::Left) | Op::infix(Rule::div, Assoc::Left))
+    ;
+
+    let expr = pratt
+        .map_primary(|p| {
+            parse_single_expr(p)
+        })
+        .map_infix(|lhs, op, rhs| {
+            Box::new(Expression::Binary(lhs.clone(), op.as_str().into(), rhs.clone()))
+        })
+        .parse(parsed.into_inner());
+
+    expr
+}
+
+fn parse_bindings(parsed: Pair<Rule>) -> Binding {
+    let mut p = parsed.into_inner();
+    Binding {
+        lhs: parse_identifier(p.next().unwrap()),
+        rhs: parse_expr(p.next().unwrap()),
+    }
+}
+
+fn parse_function_expr(parsed: Pair<Rule>) -> Option<Box<Expression>> {
+    let mut p = parsed.into_inner();
+    let parsed_params = p.next()?;
+    let parsed_bindings = p.next()?;
+    let parsed_body = p.next()?;
+
+    let params = parsed_params.into_inner().map(parse_identifier).collect();
+    let bindings = parsed_bindings.into_inner().map(parse_bindings).collect();
+    let body = parse_expr(parsed_body);
+
+    Some(Box::new(Expression::Function(params, bindings, body)))
+}
+
+fn parse_if_expr(parsed: Pair<Rule>) -> Option<Box<Expression>> {
+    let mut p = parsed.into_inner();
+    let condition = parse_expr(p.next()?);
+    let ifbranch = parse_expr(p.next()?);
+    let elsebranch = parse_expr(p.next()?);
+    Some(Box::new(Expression::IfClause(condition, ifbranch, elsebranch)))
+}
+
+fn parse_call_expr(parsed: Pair<Rule>) -> Option<Box<Expression>> {
+    let mut p = parsed.into_inner();
+    let identifier = parse_identifier(p.next()?);
+    let parsed_params = p.next()?;
+    let params = parsed_params.into_inner().map(parse_expr).collect();
+    Some(Box::new(Expression::Application(identifier, params)))
+}
+
+fn parse_single_expr(parsed: Pair<Rule>) -> Box<Expression> {
+    match parsed.as_rule() {
+        Rule::if_expr => {
+            parse_if_expr(parsed).unwrap()
+        },
+        Rule::call_expr => {
+            parse_call_expr(parsed).unwrap()
+        },
+        Rule::identifier => {
+            Box::new(Expression::Identifier(parse_identifier(parsed)))
+        },
+        Rule::number => {
+            let num = parsed.as_str();
+            Box::new(Expression::Number(num.parse().unwrap()))
+        },
+        // Rule::string => {},
+        Rule::bool => {
+            if parsed.as_str() == "false" {
+                Box::new(Expression::Bool(false))
+            } else {
+                Box::new(Expression::Bool(true))
+            }
+        },
+        Rule::tuple => {
+            let mut tuple = Vec::new();
+            let mut p = parsed.into_inner();
+            while let Some(e) = p.next() {
+                tuple.push(parse_expr(e));
+            }
+            Box::new(Expression::Tuple(tuple))
+        }
+        Rule::function => {
+            parse_function_expr(parsed).unwrap()
+        }
+        Rule::expr => {
+            let e = parsed.into_inner().next().unwrap();
+            parse_expr(e)
+        },
+        _ => {
+            println!("please implement parse expr for {:?}", parsed.as_rule());
+            unreachable!();
+        }
+    }
+}
+
+fn parse_identifier(parsed: Pair<Rule>) -> Identifier {
+    Identifier { name: parsed.as_str().into() }
+}
+
+fn parse_function_type(parsed: Pair<Rule>) -> Option<Type> {
+    let mut p = parsed.into_inner();
+    let parsed_params_type = p.next()?;
+    let parsed_return_type = p.next()?;
+
+    let params_type = parsed_params_type.into_inner().map(parse_type).collect();
+    let return_type = Box::new(parse_type(parsed_return_type));
+    Some(Type::Function(params_type, return_type))
+}
+
+fn parse_type(parsed: Pair<Rule>) -> Type {
+    match parsed.as_rule() {
+        Rule::type_bool => Type::Bool,
+        Rule::type_string => Type::String,
+        Rule::type_number => Type::Number,
+        Rule::tuple_type => {
+            let mut tuple = Vec::new();
+            let mut p = parsed.into_inner();
+            while let Some(t) = p.next() {
+                tuple.push(parse_type(t));
+            }
+            Type::Tuple(tuple)
+        }
+        Rule::type_name => {
+            Type::Identifier(parse_identifier(parsed))
+        }
+        Rule::function_type => {
+            parse_function_type(parsed).unwrap()
+        }
+        _ => {
+            println!("implement parse type for {:?}", parsed.as_rule());
+            unreachable!();
+        }
+    }
+}
+
+fn parse_declaration(parsed: Pair<Rule>) -> Declaration {
+    match parsed.as_rule() {
+        Rule::type_declaration => {
+            let mut p = parsed.into_inner();
+            let identifier = p.next().unwrap();
+            let typ = p.next().unwrap();
+
+            let id = parse_identifier(identifier);
+            let t = parse_type(typ);
+
+            Declaration::Type(id, t)
+        },
+        Rule::variable_declaration => {
+            let mut p = parsed.into_inner();
+            let identifier = p.next().unwrap();
+            let typ = p.next().unwrap();
+            let definition = p.next().unwrap();
+
+            let id = parse_identifier(identifier);
+            let t = parse_type(typ);
+            let d = parse_definition(definition);
+
+            Declaration::Variable(id, t, d)
+        }
+        _ => {
+            unreachable!();
+        }
+    }
+}
+
+fn parse_module_declaration(parsed: Pair<Rule>) -> Option<ModuleInformation> {
+    let mut p = parsed.into_inner();
+    let name = parse_identifier(p.next()?);
+
+    let export_import_list = p.next()?;
+
+    let mut export_list = Vec::new();
+    let mut import_list: HashMap<Identifier, Import> = HashMap::new();
+
+    export_import_list.into_inner().for_each(|item| {
+        match item.as_rule() {
+            Rule::module_export => {
+                item.into_inner().for_each(|export| {
+                    export_list.push(parse_identifier(export))
+                });
+            }
+            Rule::module_import => {
+                let mut p = item.into_inner();
+                let name = parse_identifier(p.next().unwrap());
+                let import = {
+                    match import_list.get_mut(&name) {
+                        Some(import) => import,
+                        None => {
+                            import_list.insert(name.clone(), Import {
+                                from: name.clone(),
+                                rename: name.clone(),
+                                imported: Vec::new(),
+                            });
+                            import_list.get_mut(&name).unwrap()
+                        }
+                    }
+                };
+                if let Some(type_import) = p.next() {
+                    match type_import.as_rule() {
+                        Rule::import_selective => {
+                            let imported = type_import.into_inner().map(parse_identifier).collect();
+                            import.imported = imported;
+                        },
+                        Rule::import_change_name => {
+                            import.rename = parse_identifier(type_import.into_inner().next().unwrap());
+                        },
+                        _ => unreachable!(),
+                    }
+                }
+            }
+            _ => {
+                unreachable!();
+            }
+        }
+    });
+
+    let export = {
+        if export_list.is_empty() {
+            Export::All
+        } else {
+            Export::Selective(export_list)
+        }
+    };
+    Some(ModuleInformation {
+        name,
+        export,
+        import: import_list.into_values().collect(),
+    })
+}
+
+pub fn parse_module(parsed: Pair<Rule>) -> Option<Module> {
+    let mut p = parsed.into_inner();
+
+    let module = p.next()?;
+    let module_info = parse_module_declaration(module)?;
+
+    let mut declaration_list = Vec::new();
+    while let Some(declaration) = p.next() {
+        let declare = parse_declaration(declaration);
+        declaration_list.push(declare);
+    }
+
+    Some(Module {
+        module: module_info,
+        declaration: declaration_list,
+    })
 }

src/main.rs

@@ -1,6 +1,6 @@
 mod albireo;
 
-use crate::albireo::{AlbireoParser, Rule};
+use crate::albireo::{AlbireoParser, Rule, parse_module};
 
 use std::fs;
 use pest::Parser;
@@ -8,10 +8,11 @@ use pest::Parser;
 fn main() {
     let input = fs::read_to_string("test/simple/main.air").expect("cannot read file");
 
-    let program = AlbireoParser::parse(Rule::program, &input)
+    let parsed = AlbireoParser::parse(Rule::program, &input)
         .expect("file format is wrong or the parser is wrong")
         .next()
         .expect("cannot parse input file as a Albireo program");
 
-    println!("{:?}", program);
+    let module = parse_module(parsed);
+    println!("{:?}", module);
 }

test/simple/main.air

@@ -1,9 +1,44 @@
+; declare a module
 module main
 
-c : fn => bool = function is
-  let a = b in
-  c(a)
+; no explicit export so everything in this module is exported
+export one, two
 
-b : bool = false
+; no import
+import a
+import a only name, name
+import a as change_name
 
-a : number = 1
+; declare a variable
+one : number = 1
+
+; declare a variable that is computed
+; places a burden on the runtime
+two : number = one + 1
+
+; tt : bool = true
+
+; types can be named, alias
+
+; using tuple or record or enum
+type coordinates_tuple = tuple (number, number)
+; type coordinates_record = record { x : number , y : number }
+
+coordinates_as_tuple : coordinates_tuple = tuple (1, 2)
+; coordinates_as_record : coordinates_record = record { x : 1 , y : 2 }
+
+; function definition is structured the same
+void : fn => number = function is
+  let x = 1 in
+  1
+
+return_false : fn => bool = function is
+  false
+
+increment : fn number => number = function x is
+  x + 1
+
+is_even : fn number => bool = function x is
+  if x % 2 then true else false
+
+bruh : number = increment(one)