fmt: fix formatting of anon args (#6545)

vlib/os/os_nix.c.v

@@ -28,7 +28,7 @@ mut:
 
 fn C.uname(name voidptr) int
 
-fn C.symlink(arg_1, arg_2 charptr) int
+fn C.symlink(charptr, charptr) int
 
 pub fn uname() Uname {
 	mut u := Uname{}

vlib/pg/pg.v

@@ -30,23 +30,23 @@ pub:
 
 fn C.PQconnectdb(a byteptr) &C.PGconn
 
-fn C.PQerrorMessage(arg_1 voidptr) byteptr
+fn C.PQerrorMessage(voidptr) byteptr
 
-fn C.PQgetvalue(arg_1 voidptr, arg_2, arg_3 int) byteptr
+fn C.PQgetvalue(voidptr, int, int) byteptr
 
-fn C.PQstatus(arg_1 voidptr) int
+fn C.PQstatus(voidptr) int
 
-fn C.PQntuples(arg_1 voidptr) int
+fn C.PQntuples(voidptr) int
 
-fn C.PQnfields(arg_1 voidptr) int
+fn C.PQnfields(voidptr) int
 
-fn C.PQexec(arg_1 voidptr) voidptr
+fn C.PQexec(voidptr) voidptr
 
-fn C.PQexecParams(arg_1 voidptr) voidptr
+fn C.PQexecParams(voidptr) voidptr
 
-fn C.PQclear(arg_1 voidptr) voidptr
+fn C.PQclear(voidptr) voidptr
 
-fn C.PQfinish(arg_1 voidptr)
+fn C.PQfinish(voidptr)
 
 // connect makes a new connection to the database server using
 // the parameters from the `Config` structure, returning

vlib/v/ast/str.v

@@ -64,7 +64,8 @@ pub fn (node &FnDecl) stringify(t &table.Table, cur_mod string) string {
 			continue
 		}
 		is_last_arg := i == node.params.len - 1
-		should_add_type := is_last_arg || node.params[i + 1].typ != arg.typ ||
+		is_type_only := arg.name == ''
+		should_add_type := is_last_arg || is_type_only || node.params[i + 1].typ != arg.typ ||
 			(node.is_variadic && i == node.params.len - 2)
 		if arg.is_mut {
 			f.write(arg.typ.share().str() + ' ')
@@ -79,11 +80,13 @@ pub fn (node &FnDecl) stringify(t &table.Table, cur_mod string) string {
 		}
 		s = util.no_cur_mod(s, cur_mod)
 		if should_add_type {
-			if node.is_variadic && is_last_arg {
+			if !is_type_only {
-				f.write(' ...' + s)
+				f.write(' ')
-			} else {
-				f.write(' ' + s)
 			}
+			if node.is_variadic && is_last_arg {
+				f.write('...')
+			}
+			f.write(s)
 		}
 		if !is_last_arg {
 			f.write(', ')

vlib/v/fmt/tests/fn_with_anon_params_keep.vv

@@ -0,0 +1 @@
+fn C.PQgetvalue(voidptr, int, int) byteptr

vlib/v/gen/fn.v

@@ -208,7 +208,6 @@ fn (mut g Gen) write_defer_stmts_when_needed() {
 fn (mut g Gen) fn_args(args []table.Param, is_variadic bool) ([]string, []string) {
 	mut fargs := []string{}
 	mut fargtypes := []string{}
-	no_names := args.len > 0 && args[0].name == 'arg_1'
 	for i, arg in args {
 		caname := c_name(arg.name)
 		typ := g.unwrap_generic(arg.typ)
@@ -245,11 +244,6 @@ fn (mut g Gen) fn_args(args []table.Param, is_variadic bool) ([]string, []string
 				g.write(')')
 				g.definitions.write(')')
 			}
-		} else if no_names {
-			g.write(arg_type_name)
-			g.definitions.write(arg_type_name)
-			fargs << ''
-			fargtypes << arg_type_name
 		} else {
 			mut nr_muls := arg.typ.nr_muls()
 			s := arg_type_name + ' ' + caname

vlib/v/gen/js/js.v

@@ -900,7 +900,6 @@ fn (mut g JsGen) gen_method_decl(it ast.FnDecl) {
 }
 
 fn (mut g JsGen) fn_args(args []table.Param, is_variadic bool) {
-	// no_names := args.len > 0 && args[0].name == 'arg_1'
 	for i, arg in args {
 		name := g.js_name(arg.name)
 		is_varg := i == args.len - 1 && is_variadic

vlib/v/parser/fn.v

@@ -253,6 +253,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 	// Args
 	args2, are_args_type_only, is_variadic := p.fn_args()
 	params << args2
+	if !are_args_type_only {
 		for param in params {
 			if p.scope.known_var(param.name) {
 				p.error_with_pos('redefinition of parameter `$param.name`', param.pos)
@@ -266,6 +267,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 				is_arg: true
 			})
 		}
+	}
 	mut end_pos := p.prev_tok.position()
 	// Return type
 	mut return_type := table.void_type
@@ -430,7 +432,6 @@ fn (mut p Parser) fn_args() ([]table.Param, bool, bool) {
 		// p.warn('types only')
 		mut arg_no := 1
 		for p.tok.kind != .rpar {
-			arg_name := 'arg_$arg_no'
 			is_shared := p.tok.kind == .key_shared
 			is_atomic := p.tok.kind == .key_atomic
 			is_mut := p.tok.kind == .key_mut || is_shared || is_atomic
@@ -480,7 +481,7 @@ fn (mut p Parser) fn_args() ([]table.Param, bool, bool) {
 			sym := p.table.get_type_symbol(arg_type)
 			args << table.Param{
 				pos: pos
-				name: arg_name
+				name: ''
 				is_mut: is_mut
 				typ: arg_type
 				type_source_name: sym.source_name