Add stream.er

compiler/erg_compiler/hir.rs

@@ -1081,8 +1081,13 @@ pub struct Call {
 
 impl NestedDisplay for Call {
     fn fmt_nest(&self, f: &mut std::fmt::Formatter<'_>, level: usize) -> std::fmt::Result {
-        writeln!(f, "({}){}:", self.obj, fmt_option!(self.attr_name),)?;
+        writeln!(f, "({}){}", self.obj, fmt_option!(self.attr_name),)?;
-        self.args.fmt_nest(f, level + 1)
+        if self.args.is_empty() {
+            write!(f, "()")
+        } else {
+            writeln!(f, ":")?;
+            self.args.fmt_nest(f, level + 1)
+        }
     }
 }
 

compiler/erg_parser/ast.rs

@@ -1017,8 +1017,12 @@ impl NestedDisplay for Call {
         if let Some(attr_name) = self.attr_name.as_ref() {
             write!(f, "{}", attr_name)?;
         }
-        writeln!(f, ":")?;
+        if self.args.is_empty() {
-        self.args.fmt_nest(f, level + 1)
+            write!(f, "()")
+        } else {
+            writeln!(f, ":")?;
+            self.args.fmt_nest(f, level + 1)
+        }
     }
 }
 

compiler/erg_parser/parse.rs

@@ -2170,14 +2170,17 @@ impl Parser {
     /// x |> f() => f(x)
     fn try_reduce_stream_operator(&mut self, stack: &mut Vec<ExprOrOp>) -> ParseResult<()> {
         debug_call_info!(self);
-        self.skip(); // |> 
+        self.skip(); // |>
 
         fn get_stream_op_syntax_error(loc: Location) -> ParseError {
-            ParseError::syntax_error(0, loc, switch_lang!(
+            ParseError::syntax_error(
-                "japanese" => "パイプ演算子の後には関数・メソッド・サブルーチン呼び出しのみが使用できます。",
+                0,
-                "english" => "Only a call of function, method or subroutine is available after stream operator.",
+                loc,
-            ),
+                switch_lang!(
-            None
+                    "japanese" => "パイプ演算子の後には関数・メソッド・サブルーチン呼び出しのみが使用できます。",
+                    "english" => "Only a call of function, method or subroutine is available after stream operator.",
+                ),
+                None,
             )
         }
 

compiler/erg_parser/tests/stream.er

@@ -0,0 +1,2 @@
+print!(1 + 1 |> f())
+print!(1 + 1 |> .abs())