parser: use a token.KeywordsMatcherTrie matching checks, instead of the map checks for name in p.imported_symbols

vlib/v/parser/enum.v

@@ -61,7 +61,7 @@ fn (mut p Parser) enum_decl() ast.EnumDecl {
 			end_pos)
 		return ast.EnumDecl{}
 	}
-	if enum_name in p.imported_symbols {
+	if p.is_imported_symbol(enum_name) {
 		p.error_with_pos('cannot register enum `${enum_name}`, this type was already imported',
 			end_pos)
 		return ast.EnumDecl{}

vlib/v/parser/fn.v

@@ -89,7 +89,7 @@ fn (mut p Parser) call_expr(language ast.Language, mod string) ast.CallExpr {
 		}
 		or_kind = if is_not { .propagate_result } else { .propagate_option }
 	}
-	if fn_name in p.imported_symbols {
+	if p.is_imported_symbol(fn_name) {
 		check := !p.imported_symbols_used[fn_name]
 		fn_name = p.imported_symbols[fn_name]
 		if check {
@@ -393,7 +393,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 			}
 		}
 		if !p.pref.is_fmt {
-			if name in p.imported_symbols {
+			if p.is_imported_symbol(name) {
 				p.error_with_pos('cannot redefine imported function `${name}`', name_pos)
 				return ast.FnDecl{
 					scope: unsafe { nil }

vlib/v/parser/module.v

@@ -36,7 +36,7 @@ fn (mut p Parser) register_used_import(alias string) {
 fn (mut p Parser) register_used_import_for_symbol_name(sym_name string) {
 	short_import_name := sym_name.all_before_last('.').all_after_last('.')
 	short_symbol_name := sym_name.all_after_last('.')
-	if short_symbol_name in p.imported_symbols {
+	if p.is_imported_symbol(short_symbol_name) {
 		p.imported_symbols_used[short_symbol_name] = true
 	}
 	for alias, mod in p.imports {
@@ -322,12 +322,13 @@ fn (mut p Parser) import_syms(mut parent ast.Import) {
 	for p.tok.kind == .name {
 		pos := p.tok.pos()
 		alias := p.check_name()
-		if alias in p.imported_symbols {
+		if p.is_imported_symbol(alias) {
 			p.error_with_pos('cannot register symbol `${alias}`, it was already imported',
 				pos)
 			return
 		}
 		p.imported_symbols[alias] = parent.mod + '.' + alias
+		p.rebuild_imported_symbols_matcher(alias)
 		// so we can work with this in fmt+checker
 		parent.syms << ast.ImportSymbol{
 			pos:  pos
@@ -347,3 +348,12 @@ fn (mut p Parser) import_syms(mut parent ast.Import) {
 	}
 	p.next()
 }
+
+fn (mut p Parser) rebuild_imported_symbols_matcher(name string) {
+	p.imported_symbols_trie = token.new_keywords_matcher_from_array_trie(p.imported_symbols.keys())
+}
+
+@[inline]
+fn (mut p Parser) is_imported_symbol(name string) bool {
+	return p.imported_symbols_trie.matches(name)
+}

vlib/v/parser/parse_type.v

@@ -636,7 +636,7 @@ fn (mut p Parser) parse_any_type(language ast.Language, is_ptr bool, check_dot b
 	} else if p.expr_mod != '' && !p.inside_generic_params {
 		// p.expr_mod is from the struct and not from the generic parameter
 		name = p.expr_mod + '.' + name
-	} else if name in p.imported_symbols {
+	} else if p.is_imported_symbol(name) {
 		check := !p.imported_symbols_used[name]
 		name = p.imported_symbols[name]
 		if check {

vlib/v/parser/parser.v

@@ -86,6 +86,7 @@ mut:
 	implied_imports          []string // ​imports that the user's code uses but omitted to import explicitly, used by `vfmt`
 	imported_symbols         map[string]string
 	imported_symbols_used    map[string]bool
+	imported_symbols_trie    token.KeywordsMatcherTrie
 	is_amp                   bool // for generating the right code for `&Foo{}`
 	returns                  bool
 	is_stmt_ident            bool // true while the beginning of a statement is an ident/selector
@@ -592,8 +593,7 @@ fn (mut p Parser) check_name() string {
 	name := p.tok.lit
 	if p.tok.kind != .name && p.peek_tok.kind == .dot && name in p.imports {
 		p.register_used_import(name)
-	} else if p.tok.kind == .name && p.peek_tok.kind == .dot && name in p.imported_symbols
+	} else if p.tok.kind == .name && p.is_imported_symbol(name) && !p.imported_symbols_used[name] {
-		&& !p.imported_symbols_used[name] {
 		// symbols like Enum.field_name
 		p.register_used_import_for_symbol_name(p.imported_symbols[name])
 	}
@@ -2698,7 +2698,7 @@ fn (mut p Parser) type_decl() ast.TypeDecl {
 			return ast.FnTypeDecl{}
 		}
 	}
-	if name in p.imported_symbols {
+	if p.is_imported_symbol(name) {
 		p.error_with_pos('cannot register alias `${name}`, this type was already imported',
 			end_pos)
 		return ast.AliasTypeDecl{}

vlib/v/parser/struct.v

@@ -73,7 +73,7 @@ fn (mut p Parser) struct_decl(is_anon bool) ast.StructDecl {
 		p.error_with_pos('struct names must have more than one character', name_pos)
 		return ast.StructDecl{}
 	}
-	if name in p.imported_symbols {
+	if p.is_imported_symbol(name) {
 		p.error_with_pos('cannot register struct `${name}`, this type was already imported',
 			name_pos)
 		return ast.StructDecl{}
@@ -651,7 +651,7 @@ fn (mut p Parser) interface_decl() ast.InterfaceDecl {
 	mut pre_comments := p.eat_comments()
 	p.check(.lcbr)
 	pre_comments << p.eat_comments()
-	if modless_name in p.imported_symbols {
+	if p.is_imported_symbol(modless_name) {
 		p.error_with_pos('cannot register interface `${interface_name}`, this type was already imported',
 			name_pos)
 		return ast.InterfaceDecl{}