This is an automated email from the ASF dual-hosted git repository.
asf-gitbox-commits pushed a commit to branch asf-site
in repository https://gitbox.apache.org/repos/asf/groovy-dev-site.git
The following commit(s) were added to refs/heads/asf-site by this push:
new 37d15fd 2026/05/19 23:40:06: Generated dev website from
groovy-website@f579edf
37d15fd is described below
commit 37d15fd75141f7d7e201f1573afb7c4d7338fad8
Author: jenkins <[email protected]>
AuthorDate: Tue May 19 23:40:06 2026 +0000
2026/05/19 23:40:06: Generated dev website from groovy-website@f579edf
---
search/search-index.json | 2 +-
wiki/GEP-23.html | 129 ++++++++++++++++++++++++++++++++++++-----------
2 files changed, 101 insertions(+), 30 deletions(-)
diff --git a/search/search-index.json b/search/search-index.json
index 6adce2c..c846ee2 100644
--- a/search/search-index.json
+++ b/search/search-index.json
@@ -926,7 +926,7 @@
{
"id": "wiki/GEP-23.html",
"title": "The Apache Groovy programming language - Developer docs -
GEP-23",
- "content": "The Apache Groovy programming language - Developer docs -
GEP-23 Socialize Discuss on the mailing list Groovy on X Groovy on Bluesky
Groovy on Mastodon Groovy on LinkedIn Events and conferences Source code on
GitHub Report issues in Jira Stack Overflow questions Slack Community You are
using an outdated browser. Please upgrade your browser to improve your
experience. Apache Groovy™ Learn Documentation Download Support
Contribute Ecosystem Blog posts Socialize GE [...]
+ "content": "The Apache Groovy programming language - Developer docs -
GEP-23 Socialize Discuss on the mailing list Groovy on X Groovy on Bluesky
Groovy on Mastodon Groovy on LinkedIn Events and conferences Source code on
GitHub Report issues in Jira Stack Overflow questions Slack Community You are
using an outdated browser. Please upgrade your browser to improve your
experience. Apache Groovy™ Learn Documentation Download Support
Contribute Ecosystem Blog posts Socialize GE [...]
"url": "wiki/GEP-23.html",
"site": "dev"
},
diff --git a/wiki/GEP-23.html b/wiki/GEP-23.html
index bf88aeb..6031729 100644
--- a/wiki/GEP-23.html
+++ b/wiki/GEP-23.html
@@ -91,7 +91,7 @@
<strong>Version</strong>
</td>
<td class="hdlist2">
-<p>1</p>
+<p>2</p>
</td>
</tr>
<tr>
@@ -139,7 +139,7 @@
<strong>Last modification</strong>
</td>
<td class="hdlist2">
-<p>2026-05-19</p>
+<p>2026-05-20</p>
</td>
</tr>
</table>
@@ -161,7 +161,7 @@ Haskell-style do-notation ergonomics for any type with
monadic shape —
that opt in.</p>
</div>
<div class="paragraph">
-<p>Three artefacts are introduced:</p>
+<p>The following artefacts are introduced:</p>
</div>
<div class="ulist">
<ul>
@@ -174,9 +174,14 @@ rewrite at compile time;</p>
and may declare non-conventional bind/map method names;</p>
</li>
<li>
-<p>a type-checking extension that enforces the monadic shape under
-<code>@CompileStatic</code>/<code>@TypeChecked</code> and supplies the static
types that flow
-through the rewritten chain.</p>
+<p><code>groovy.typecheckers.MonadicChecker</code> — a type-checking extension
that
+enforces the monadic shape under
<code>@CompileStatic</code>/<code>@TypeChecked</code> and supplies
+the static types that flow through the rewritten chain;</p>
+</li>
+<li>
+<p><code>groovy.typecheckers.MonadicShapeChecker</code> — a sibling
type-checking
+extension that lints hand-written <code>flatMap</code>/<code>map</code> chains
over the same
+carrier set, independent of <code>DO</code>.</p>
</li>
</ul>
</div>
@@ -445,6 +450,8 @@ by simple name, in the manner of
<code>@Reducer</code>/<code>@Associative</code>
value that does not respond to the resolved bind method fails at runtime
with the usual <code>MissingMethodException</code>.</p>
</div>
+<div class="sect3">
+<h4 id="_do_under_static_compilation_monadicchecker"><code>DO</code> under
static compilation: <code>MonadicChecker</code></h4>
<div class="paragraph">
<p>Under <code>@CompileStatic</code>/<code>@TypeChecked</code>, the
<code>groovy.typecheckers.MonadicChecker</code>
type-checking extension (GEP-8) is activated via the <code>extensions</code>
member:</p>
@@ -470,7 +477,17 @@ body type-checks;</p>
</li>
<li>
<p>restores the comprehension’s result type, so chained and nested use
-type-checks rather than degrading to <code>Object</code>.</p>
+type-checks rather than degrading to <code>Object</code>;</p>
+</li>
+<li>
+<p>for <strong>trusted</strong> carriers (allow-list or
<code>@Monadic</code>), enforces the
+closure-return contract that the dispatcher’s erased
+<code>(Object, Closure):Object</code> signature hides from STC: a
<code>bind</code> closure must
+yield the same carrier (catching a bare-value body and a cross-carrier
+body, including in nested <code>DO</code>), and a hand-written
<code>Comprehensions.map</code>
+closure must not yield the same carrier (catching the
<code>M<M<T>></code> foot-gun).
+Structural-only carriers are not asserted against, matching the permissive
+treatment of participation.</p>
</li>
</ul>
</div>
@@ -480,6 +497,55 @@ earlier bound name) and nested comprehensions are
supported under static
compilation.</p>
</div>
</div>
+<div class="sect3">
+<h4 id="_native_chains_monadicshapechecker">Native chains:
<code>MonadicShapeChecker</code></h4>
+<div class="paragraph">
+<p>A sibling extension <code>groovy.typecheckers.MonadicShapeChecker</code>
lints
+hand-written
<code>flatMap</code>/<code>map</code>/<code>thenCompose</code>/<code>thenApply</code>
chains over the same
+carrier set. It is independent of <code>DO</code>; use it on codebases that
mix or
+favour native chains.</p>
+</div>
+<div class="listingblock">
+<div class="content">
+<pre class="prettyprint highlight"><code
data-lang="groovy">@CompileStatic(extensions =
'groovy.typecheckers.MonadicShapeChecker')</code></pre>
+</div>
+</div>
+<div class="paragraph">
+<p>It flags three high-confidence problems:</p>
+</div>
+<div class="ulist">
+<ul>
+<li>
+<p><code>bind</code> returning a non-carrier — e.g. <code>Optional.flatMap {
it + 1 }</code>,
+where Groovy’s SAM coercion can let an Integer-returning closure slip
past
+STC;</p>
+</li>
+<li>
+<p><code>bind</code> returning a different carrier — e.g.
+<code>Stream.flatMap { Optional.of(it) }</code>;</p>
+</li>
+<li>
+<p><code>map</code> returning the same carrier — e.g.
+<code>Optional.map { Optional.of(it) }</code>, the classic
<code>M<M<T>></code> foot-gun.</p>
+</li>
+</ul>
+</div>
+<div class="paragraph">
+<p>Carriers and method-name conventions are read from the same registry as
+<code>MonadicChecker</code>; <code>@Monadic</code>-annotated types also
participate. Calls routed
+through the bind/map dispatcher are skipped (that is `MonadicChecker’s
+domain). A strict mode additionally flags chains whose function-return type
+cannot be statically resolved.</p>
+</div>
+<div class="paragraph">
+<p>The two extensions are complementary but independent:
<code>MonadicChecker</code>
+repairs erasure on the <code>DO</code>-macro dispatcher and asserts the
dispatcher’s
+closure-return shape; <code>MonadicShapeChecker</code> asserts the same shape
on
+native chains the dispatcher never sees. Code that mixes <code>DO</code> with
native
+chains may opt into both.</p>
+</div>
+</div>
+</div>
<div class="sect2">
<h3 id="_scoping_return_break_continue">Scoping, <code>return</code>,
<code>break</code>, <code>continue</code></h3>
<div class="paragraph">
@@ -698,11 +764,13 @@ and structural matching alone is too narrow.</p>
<td class="tableblock halign-left valign-top"><p
class="tableblock">2026</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Initial
release (incubating). The <code>DO</code> macro; the bind/map dispatcher and
carrier registry in the core runtime; <code>@groovy.transform.Monadic</code>;
the
-<code>groovy.typecheckers.MonadicChecker</code> type-checking extension; the
standard
-allow-list (<code>Optional</code>, <code>Stream</code>,
<code>CompletableFuture</code>, <code>CompletionStage</code>,
-<code>Awaitable</code>, <code>DataflowVariable</code>) and the by-name
recognition of common
-Functional Java carriers; general single-abstract-method coercion of the
-generator closure.</p></td>
+<code>groovy.typecheckers.MonadicChecker</code> type-checking extension
(participation,
+inference, and closure-return shape under <code>@CompileStatic</code>); the
sibling
+<code>groovy.typecheckers.MonadicShapeChecker</code> extension for native
+<code>flatMap</code>/<code>map</code> chains; the standard allow-list
(<code>Optional</code>, <code>Stream</code>,
+<code>CompletableFuture</code>, <code>CompletionStage</code>,
<code>Awaitable</code>, <code>DataflowVariable</code>)
+and the by-name recognition of common Functional Java carriers; general
+single-abstract-method coercion of the generator closure.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p
class="tableblock">7.0</p></td>
@@ -827,7 +895,13 @@ optional <code>bind</code>/<code>map</code> string
attributes and no AST transfo
</li>
<li>
<p><code>groovy.typecheckers.MonadicChecker</code> — the type-checking
extension that
-enforces the monadic shape and supplies static types under
<code>@CompileStatic</code>.</p>
+enforces the receiver and closure-return monadic shape and supplies static
+types under <code>@CompileStatic</code>.</p>
+</li>
+<li>
+<p><code>groovy.typecheckers.MonadicShapeChecker</code> — sibling type-checking
+extension that lints hand-written native <code>flatMap</code>/<code>map</code>
chains against the
+same carrier set; independent of <code>DO</code>.</p>
</li>
</ul>
</div>
@@ -846,6 +920,10 @@ enforces the monadic shape and supplies static types under
<code>@CompileStatic<
<p><code>groovy.typecheckers.MonadicChecker</code>, in the
<code>groovy-typecheckers</code>
module (since 6.0.0)</p>
</li>
+<li>
+<p><code>groovy.typecheckers.MonadicShapeChecker</code>, in the
<code>groovy-typecheckers</code>
+module (since 6.0.0)</p>
+</li>
</ul>
</div>
</div>
@@ -854,22 +932,7 @@ module (since 6.0.0)</p>
<div class="ulist">
<ul>
<li>
-<p>GROOVY-XXXX: introduce the <code>DO</code> monadic-comprehension macro.</p>
-</li>
-<li>
-<p>GROOVY-XXXX: bind/map dispatcher and carrier registry in the core
-runtime.</p>
-</li>
-<li>
-<p>GROOVY-XXXX: <code>@groovy.transform.Monadic</code> annotation.</p>
-</li>
-<li>
-<p>GROOVY-XXXX: <code>groovy.typecheckers.MonadicChecker</code> type-checking
-extension.</p>
-</li>
-<li>
-<p>GROOVY-XXXX: language-specification chapter with inline-tested examples
-and the tool-selection matrix row.</p>
+<p>GROOVY-12021: Initial implementation of the <code>DO</code>
monadic-comprehension macro and related type checkers.</p>
</li>
</ul>
</div>
@@ -880,6 +943,14 @@ and the tool-selection matrix row.</p>
<h2 id="_update_history">Update history</h2>
<div class="sectionbody">
<div class="paragraph">
+<p>2 (2026-05-20) Adds closure-return shape enforcement to
<code>MonadicChecker</code>
+(rejects bare-value and cross-carrier <code>DO</code> bodies for trusted
carriers via
+the dispatcher); introduces the sibling
+<code>groovy.typecheckers.MonadicShapeChecker</code> extension for native
+<code>flatMap</code>/<code>map</code>/<code>thenCompose</code>/<code>thenApply</code>
chains across the same carrier
+set.</p>
+</div>
+<div class="paragraph">
<p>1 (2026-05-19) Initial draft. Specifies the <code>DO</code> macro, the
<code>@Monadic</code>
annotation, the type-checking extension, the standard carrier allow-list
(including by-name recognition of Functional Java), the runtime model and
