Rename scanner-common::capture_token to capture and remove old

`capture` Fixes #200.
foonathan · May 21, 2024 · 1e5d99f · 1e5d99f
1 parent e8eb4d6
commit 1e5d99f
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Showing 4 changed files with 42 additions and 20 deletions.
diff --git a/CHANGELOG.adoc b/CHANGELOG.adoc
@@ -4,12 +4,14 @@
 
 === Potential breaking changes
 
+* `scanner-common::capture_token` was renamed to `scanner-common::capture`, and old `scanner-common::capture` removed.
+  Previously, `capture_token` was a linker error anyway, but if you're calling `scanner-common::capture` it will no longer work for arbitrary rules and instead only like `dsl::capture`.
 * `lexy::parse_as_tree` will add a position token to production nodes that would otherwise be empty.
   That way, no production node will be empty, unless the builder API is used directly.
 * Change `lexy::dsl::try_()` error recovery behavior:
   It will now skip whitespace after the (optional) error recovery rule.
 * Deprecate the `lexy::parse_tree::builder::finish()` overload that does not take a `remaining_input`.
-* The typo `lexy::code_point::spaing_mark` was fixed to `lexy::code_point::spacing_mark`.
+* The typo `lexy::code_point::spaing_mark` was fixed to `spacing_mark`.
 
 === New Features
 

diff --git a/docs/content/reference/action/scan.adoc b/docs/content/reference/action/scan.adoc
@@ -136,10 +136,8 @@ namespace lexy
         template <typename T>
         constexpr scan_result<T> integer(_ndigits-dsl_ digits);
 
-        // Forwards to `parse(rule)` (without value!) and then returns a lexeme.
+        // Forwards to `parse(result, dsl::capture(rule))`.
         constexpr scan_result<lexeme<Reader>> capture(_rule_ auto rule);
-        // Forwards to `parse(result, dsl::capture_token(rule))`.
-        constexpr scan_result<lexeme<Reader>> capture_token(_token-rule_ auto rule);
     };
 }
 ----

diff --git a/include/lexy/dsl/scan.hpp b/include/lexy/dsl/scan.hpp
@@ -18,7 +18,9 @@ struct _prd;
 template <typename Rule, typename Tag>
 struct _peek;
 template <typename Token>
-struct _capt;
+struct _cap;
+template <typename Rule>
+struct _capr;
 template <typename T, typename Base>
 struct _int_dsl;
 
@@ -379,25 +381,18 @@ class scanner
         return result;
     }
 
-    template <typename Rule>
-    constexpr auto capture(Rule rule) -> scan_result<lexeme<Reader>>
+    template <typename Token>
+    constexpr auto capture(Token)
     {
-        static_assert(lexy::is_rule<Rule>);
-
-        auto begin = _reader.position();
-        parse(rule);
-        auto end = _reader.position();
-
-        if (*this)
-            return lexeme<Reader>(begin, end);
-        else
-            return scan_failed;
+        scan_result<lexeme<Reader>> result;
+        parse(result, lexyd::_cap<Token>{});
+        return result;
     }
-    template <typename Token>
-    constexpr auto capture_token(Token)
+    template <typename Production>
+    constexpr auto capture(lexyd::_prd<Production>)
     {
         scan_result<lexeme<Reader>> result;
-        parse(result, lexyd::_capt<Token>{});
+        parse(result, lexyd::_capr<lexyd::_prd<Production>>{});
         return result;
     }
 

diff --git a/tests/lexy/action/scan.cpp b/tests/lexy/action/scan.cpp
@@ -26,6 +26,11 @@ struct production
         = lexy::callback<int>([](auto lex) { return static_cast<int>(lex.size()); });
 };
 
+struct token_production : lexy::token_production
+{
+    static constexpr auto rule = LEXY_LIT("abc");
+};
+
 struct control_production
 {
     static constexpr auto whitespace = LEXY_LIT(" ");
@@ -388,5 +393,27 @@ TEST_CASE("lexy::scan")
         CHECK(scanner);
         check_position(scanner, true, input.data() + 7);
     }
+
+    SUBCASE("capture")
+    {
+        auto input   = lexy::zstring_input("abcabc");
+        auto scanner = lexy::scan(input, errors);
+        CHECK(scanner);
+        check_position(scanner, false, input.data());
+
+        auto lexeme = scanner.capture(LEXY_LIT("abc"));
+        CHECK(scanner);
+        check_position(scanner, false, input.data() + 3);
+        CHECK(lexeme);
+        CHECK(lexeme.value().begin() == input.data());
+        CHECK(lexeme.value().end() == input.data() + 3);
+
+        lexeme = scanner.capture(lexy::dsl::p<token_production>);
+        CHECK(scanner);
+        check_position(scanner, true, input.data() + 6);
+        CHECK(lexeme);
+        CHECK(lexeme.value().begin() == input.data() + 3);
+        CHECK(lexeme.value().end() == input.data() + 6);
+    }
 }