R4: one argument form (Param = expr) and with ({n} = …) text templates (#751)

.claude/skills/fix-issue/findings/mdl-executor.jsonl

@@ -735,3 +735,4 @@
 {"area": "mdl/executor", "date": "2026-09-27", "symptom": "describe of a published REST service with no resources printed `create or modify published rest service M.S ( \u2026 )` followed by a bare `;`, which does not parse (`mismatched input ';' expecting '{'`); found while making describe end every statement with `;` (ako/mxcli#744).", "cause": "The resource block `{ \u2026 }` is mandatory in the grammar (publishedRestService: \u2026 RPAREN LBRACE publishedRestResource* RBRACE), but the describer only printed it when the service had resources and otherwise closed the statement with `;` alone.", "file": "mdl/executor/cmd_published_rest.go", "fix": "Always print the block: `{\\n};` when there are no resources.", "insight": "A describe test that asserts substrings never parses the output; feeding every Describe*_Mock output through the parser (assertTerminated, #744) found this at once. The empty-collection branch of a describer is the one no fixture exercises.", "test": "TestDescribePublishedRestService_Mock (assertTerminated)"}
 {"area": "mdl/executor", "date": "2026-09-27", "symptom": "Running an external entity's describe output (create or modify external entity, either form) turns each attribute's Rest$ODataMappedValue into a DomainModels$StoredValue (RemoteName/RemoteType/Filterable... gone), re-mints attribute $IDs on the `from odata client` form, and rewrites String(36) as unlimited", "cause": "Both rewrite paths rebuilt attributes from the AST, which has no spelling for the OData mapping; the `from odata client` path minted fresh IDs; describe external entity printed GetTypeName() (`String`) instead of formatAttributeType", "file": "mdl/executor/cmd_entities.go (carryStoredAttributeState), cmd_odata.go", "insight": "Carry per attribute by name what the statement cannot spell, in the shared merge, and enumerate every path that rebuilds attributes: there were two statements for one document kind", "refs": ["ako/mxcli#743"]}
 {"area": "mdl/executor", "date": "2026-09-27", "symptom": "create or modify odata service over a Studio Pro service: EntitySet PageSize 10000 -> 0, entity sets reordered, member CanBeEmpty recomputed, ExportLevel deleted, AuthenticationTypes marker 1 -> 3", "cause": "The modify path rebuilt entity types/sets from the publish block (no spelling for PageSize without paging, set order, CanBeEmpty); the model had no ExportLevel; the writer used a marker-3 list copied from the legacy writer, not Studio Pro", "file": "mdl/executor/cmd_odata.go (carryPublishedEntityState), mdl/backend/modelsdk/odata_write.go", "insight": "Parity with the legacy writer is not evidence of what Studio Pro writes; measure markers on a Studio Pro fixture. A probe that runs describe output with the verb rewritten to create or modify (mdl/roundtrip TestTestAppCreateOrModifyProbe) shows what a verb switch would lose before switching it", "refs": ["ako/mxcli#743"]}
+{"area": "mdl/executor", "date": "2026-09-27", "symptom": "describe microflow printed `validation feedback $O/A message '{1} \u2026';` with no template arguments; describe -> exec stored the feedback with none", "cause": "formatAction's ValidationFeedbackAction case never read TemplateParameters, although the reader (textTemplateFromGen) and the writer both carried them", "file": "mdl/executor/cmd_microflows_format_action.go (templateArgsClause)", "insight": "A text template has two halves, the text and its parameters; check every describe case that prints one prints both. Found while switching the template form to `with ({1} = \u2026)` (ako/mxcli#751)."}

.claude/skills/fix-issue/findings/mdl-visitor.jsonl

@@ -36,3 +36,4 @@
 {"area":"mdl-visitor","date":"2026-09-24","refs":["#653"],"symptom":"describe entity on a view entity, exec'd back, was never idempotent: \"Each cycle reports `Modified view entity` and stores the query with every line after the first indented two spaces further.\" Re-exec of the SAME described file reported Unchanged, so it looked stable until you described again","cause":"The two directions did not mirror: describe (cmd_entities_describe.go, and cmd_diff_mdl.go) prefixes two spaces to every stored OQL line; the visitor stored extractOriginalText(oqlCtx), which starts at the query's first token, so line 1 lost its indentation and lines 2…n kept all of it — +2 per cycle","file":"`mdl/visitor/visitor_entity.go` (dedentOQL, leadingLineWhitespace); tests `mdl/visitor/visitor_view_entity_oql_indent_test.go`, `mdl/executor/view_entity_oql_roundtrip_test.go`; bug-test `mdl-examples/bug-tests/653-view-entity-oql-indent-drift.mdl`","insight":"**Any verbatim-source capture that starts at the first token is asymmetric**: line 1 is dedented for free, the continuation lines are not. Fix it on the way IN (exec), not by making describe emit less: strip the common leading-whitespace prefix of the non-blank lines, counting line 1 at its column when only whitespace precedes it (read it from the input stream, start.GetStart()-GetColumn()). Compare prefixes byte-wise, not by width, so a Studio Pro query indented with tabs comes back byte-identical under describe's two spaces. A round-trip test must run describe → exec at least twice AND start from stored text mxcli did not write (flat, tabs, blank lines, comments): one pass from a script is exactly how this went unnoticed. Control: stubbing dedentOQL to return raw fails every round-trip case with lines 2…n two spaces deeper; a real 11.12.1 project with the old binary printed Modified ×3 with growing indent, the fixed one Unchanged ×3. Separate, not fixed here: a comment AFTER the query's last token is outside the captured span and is dropped on exec"}
 {"area": "mdl/visitor", "date": "2026-09-25", "symptom": "A page action's microflow argument `Flag: true and false` was stored as the expression \"trueandfalse\", `Mode: if true then 'a' else 'b'` as \"iftruethen'a'else'b'\", and a REST call parameter `$OrderId = if $x then $id else 'none'` as \"if$xthen$idelse'none'\" (measured by decoding the units on a copy of ako/TestApp). `check -p --references` passed; describe printed the fused text back", "cause": "Four sites stored an expression as text via ANTLR's ctx.GetText(), which concatenates tokens without the hidden-channel whitespace: microflowArgV3 values (page/nanoflow call arguments), contentparams values, send-rest-request WITH parameters, and a dynamic `execute database query`. Literals, `+` and a lone $currentObject are single tokens or need no spacing, so every common case looked correct", "file": "`mdl/visitor/visitor_helpers.go` (`expressionSourceText`), `mdl/visitor/visitor_page_v3.go` (`buildMicroflowArgV3`, `buildParamAssignmentV3`), `mdl/visitor/visitor_microflow_actions.go` (dynamic query, send rest params)", "insight": "**GetText() on an expression context is always a bug** — grep `Expression().*GetText()` / `expr.GetText()` in mdl/visitor; each hit either builds the AST or must use expressionSourceText (whitespace kept, MDL comments stripped). The earlier comment-leak fix moved the six microflow sites to extractExpressionText and missed these four because they lived in page/REST code, not microflow statements: fix a text-extraction defect by searching for the call, not the feature. The tell that hid it: tests used `$currentObject` and `'a' + 'b'`, both immune; a probe with `and` / `if…then` exposed all four at once. Found while writing PROPOSAL_first_class_expressions.md §5.1. Tests `visitor_expression_source_text_test.go`", "refs": ["mendixlabs/mxcli#750"]}
 {"area": "mdl/visitor", "date": "2026-09-26", "refs": ["ako/mxcli#706"], "rules": ["MDL-IDX01", "MDL-ENUMDOC01"], "symptom": "Five forms parsed and `check` printed \"Syntax OK\", then the model lost or changed them: `throw 'x';` vanished from the microflow; `Amount: float` / `currency` became String(unlimited) (Void as a microflow type) and `date` became DateTime; `create association X (from A to B, type: referenceset, storage: table)` was stored as a Reference with column storage; a `/** … */` on an enumeration value and an index name (`index Idx on (…)`, `create index Idx on E (…)`) were read and written nowhere", "cause": "Three different gaps behind one symptom: throwStatement had a grammar rule and no listener (a whole statement); buildDataType/buildMicroflowDataType end in a default return (String / Void) that the FLOAT_TYPE and CURRENCY_TYPE tokens fell into, and DATE_TYPE mapped to an ast.TypeDate the writers alias to DateTime; ExitCreateAssociationStatement read only ctx.AssociationOptions(), while the parenthesised alternative puts its options directly under the statement as `(COMMA associationOption)*`. Enumeration-value docs and index names have no home in the metamodel (EnumerationValue and Index have no such property)", "file": "`mdl/visitor/visitor_silent_drops.go` (ExitThrowStatement, EnterDataType, EnterNonListDataType, rejectParenthesisedAssociation), `mdl/executor/validate_unstored_text.go` (MDL-IDX01, MDL-ENUMDOC01); tests `mdl/visitor/silent_drops_706_test.go`, `mdl/executor/validate_unstored_text_test.go`", "insight": "**Split by what is lost: refuse when the MODEL would be wrong, warn when only WORDS are lost.** throw/types/association write a different model, so they are visitor errors with the working spelling in the message; doc comments on values and index names leave a correct model, and were used in 56 places in our own examples, so they are check warnings. **Refuse from the parse tree, not by deleting the grammar alternative**: `float`, `currency`, `date` and `throw` are also keywords-as-identifiers, so removing `| FLOAT_TYPE` from dataType would let `Amount: float` re-parse as an enumeration reference named float — the same silence again. A listener on EnterDataType covers every place a type is written (attribute, parameter, return, declare, constant, service rules) in one method; checking only the direct child token keeps `M.Currency` and `enumeration(M.Float)` legal (the control). To find these: any `if … ; return ast.DataType{Kind: …}` fall-through default in a builder is a silent-substitution site, and a grammar alternative whose sub-rules differ from its sibling's (`associationOption` vs `associationOptions`) needs its own read. Sweep: run old vs new `mxcli check` over `git ls-files '*.mdl'` and diff exit codes — it found every example that relied on the dropped forms (5 files)"}
+{"date": "2026-09-27", "area": "mdl/visitor", "symptom": "A member path after `*`, `div`, `mod` (`$a/X * $b/Y`) is stored as division: `describe` shows `$a/X * $b / Y`, and inside a list `filter` `$b / $currentObject/Y`. `mxcli check`, `mx check` and the build are all green; Mendix evaluates a different expression.", "cause": "`/` shares a precedence level with `*`, `div`, `mod` in `multiplicativeExpression` (MDLSettings.g4), so the left-associative chain parses `$a/X * $b/Y` as `(($a/X) * $b) / Y`. `buildMultiplicativeExpression` only turned `/ Member` into an AttributePathExpr when the WHOLE left side was a variable or path; here `$b` was already the right operand of the product, so the `/` stayed a BinaryExpr. The serializer then printed a spaced `/` and the filter's `qualifyIteratorAttributes` read the stranded `Y` as a bare attribute.", "file": "mdl/visitor/visitor_microflow_expression.go (attachPathToLastOperand)", "fix": "When a `/ Member` step cannot attach to the whole left side, attach it to the last operand of the preceding multiplicative BinaryExpr (`*`, `div`, `mod`, `%`, `:`): `(L op $b) / Y` becomes `L op ($b/Y)`. Mendix has no `/` division, so `/` followed by a member name is always navigation. Division by a parenthesised expression is left alone (control test).", "insight": "Fixing it where the AST is BUILT fixes every consumer at once (serializer, iterator qualification, MDL045's slash-division check), where the earlier #52 fix only taught MDL045 to tolerate the mis-nested tree. Test: `TestMemberPathAfterMultiplicativeOperatorIsStoredAsWritten` (flow builder, stored strings for sum, filter, declare, div chain) plus a control `TestSlashAfterNonPathIsNotMadeAMemberPath`. Revert check: stubbing the fix brings back all four wrong strings. A unary-minus branch was dropped because removing it failed nothing (`2 * -$b/Y` was already stored correctly).", "refs": ["#768", "#52"], "rules": []}

.claude/skills/mendix/cheatsheet-errors/SKILL.md

@@ -265,7 +265,7 @@ Run with `-p` for the fullest coverage.
 | CE0104 | Action activity is unreachable | Code after RETURN |
 | CE0105 | Must end with end event | Missing RETURN |
 | CE0117 | Error in expression | Unqualified association path |
-| CE1571 | No argument selected for parameter | A microflow/nanoflow call with a parameter nothing fills — as a `datasource:` **or** an `action:`. Give it an argument (`action: nanoflow M.NF($P = $value)`), or nest the widget in a data container of the parameter's type. `check -p` reports both |
+| CE1571 | No argument selected for parameter | A microflow/nanoflow call with a parameter nothing fills — as a `datasource:` **or** an `action:`. Give it an argument (`action: nanoflow M.NF(P = $value)`), or nest the widget in a data container of the parameter's type. `check -p` reports both |
 | CE1571 | …in a control bar | A control bar is **not** row-scoped, so the grid's row does not fill it: pass the grid's selection (`$dgOrders`, with `Selection:` set) or move the widget into a column. `$currentObject` there is MDL-BUTTON01 |
 | CE1834 | The 'Page' property is required | Workflow user task without a `page` — `check` flags MDL-WF01 |
 | CE1876 | Single outcome must not contain activities | Single-outcome user task with a nested activity flow — `check` flags MDL-WF02 |

.claude/skills/mendix/check-syntax/SKILL.md

@@ -249,7 +249,7 @@ Before writing any MDL, verify these requirements:
 - `retrieve $Var from Module.Entity [where condition];`
 - `$Result = call microflow Module.Name (Param = $value);` (NOT `set $Result = ...`)
 - `$Result = call nanoflow Module.Name (Param = $value);`
-- `show page Module.PageName ($Param = $value);`
+- `show page Module.PageName (Param = $value);`
 - `close page;`
 - `validation feedback $entity/attribute message 'message';`
 - `log info|warning|error [node 'name'] 'message';`

.claude/skills/mendix/create-page/reference/widgets.md

@@ -123,24 +123,22 @@ describe icon collection Atlas_Core.Atlas_Filled   -- every icon + its reference
 - `action: close_page` - Close the page
 - `action: delete` - Delete object
 - `action: microflow Module.MicroflowName` - Call microflow
-- `action: microflow Module.MicroflowName(Param: $value)` - Call microflow with parameters
+- `action: microflow Module.MicroflowName(Param = $value)` - Call microflow with parameters
 - `action: nanoflow Module.NanoflowName` - Call nanoflow (client-side)
-- `action: nanoflow Module.NanoflowName(Param: $value)` - Call nanoflow with parameters
-- `action: nanoflow Module.NanoflowName($Param = $value)` - Also accepted (microflow-style)
+- `action: nanoflow Module.NanoflowName(Param = $value)` - Call nanoflow with parameters
 - `action: open_link 'https://example.com'` - Open a fixed web address
 - `action: open_link $currentObject/URL` - Open the address held in an attribute of the enclosing data container's object (inside a data container only; not over an association)
 - **Every parameter needs an argument, or an enclosing data container of its
   type.** A flow called with a parameter nothing fills is **CE1571**; `mxcli
   check -p` reports it. This is the same on every widget that takes an action,
   a clickable `container` included.
 - `action: show_page Module.PageName` - Navigate to page
-- `action: show_page Module.PageName(Param: $value)` - Navigate with parameters
-- `action: show_page Module.PageName($Param = $value)` - Also accepted (microflow-style)
+- `action: show_page Module.PageName(Param = $value)` - Navigate with parameters
 - `action: create_object Module.Entity then show_page Module.PageName` - Create and navigate
 - **A `show_page` argument must be the context object, and there has to BE one.**
   Mendix takes the page argument from the enclosing data widget, so the only
   spellings that mean anything are `$currentObject` or the name of the variable
-  that widget is bound to (`datasource: $Customer` → `(Customer: $Customer)` is
+  that widget is bound to (`datasource: $Customer` → `(Customer = $Customer)` is
   fine). Naming any other variable is refused as **MDL-PAGEARG01** — it used to be
   accepted and silently opened the page with the context object anyway.
 - **Outside a data widget the same rule leaves nothing at all**, so a button sitting
@@ -150,7 +148,7 @@ describe icon collection Atlas_Core.Atlas_Filled   -- every icon + its reference
   mxbuild reports **CE1571** per parameter of the target page, and a page whose
   parameters are optional would simply show the wrong data. MDL-PAGEARG01 refuses
   that too (mendixlabs/mxcli#1029). To open a parameterised page from such a
-  button, call a microflow that does `show page Module.Page(Param: $value)` —
+  button, call a microflow that does `show page Module.Page(Param = $value)` —
   that path wires the arguments properly.
 - **The list above is the whole vocabulary, and a keyword without its argument is
   not in it.** `action: open_link` with no URL, `action: show_page` with no page,
@@ -173,16 +171,16 @@ describe icon collection Atlas_Core.Atlas_Filled   -- every icon + its reference
 actionbutton btnSave (caption: 'Save', action: save_changes, buttonstyle: primary)
 
 -- Navigate with parameter (inside DATAVIEW)
-actionbutton btnEdit (caption: 'Edit', action: show_page Module.EditPage(Product: $Product))
+actionbutton btnEdit (caption: 'Edit', action: show_page Module.EditPage(Product = $Product))
 
 -- Navigate with $currentObject (inside DATAGRID column)
-actionbutton btnEdit (caption: 'Edit', action: show_page Module.EditPage(Product: $currentObject))
+actionbutton btnEdit (caption: 'Edit', action: show_page Module.EditPage(Product = $currentObject))
 
 -- Call microflow with page/dataview parameter
-actionbutton btnProcess (caption: 'Process', action: microflow Module.ACT_Process(Order: $Order), buttonstyle: success)
+actionbutton btnProcess (caption: 'Process', action: microflow Module.ACT_Process(Order = $Order), buttonstyle: success)
 
 -- Call microflow with $currentObject (inside DATAGRID/LISTVIEW column)
-actionbutton btnDelete (caption: 'Delete', action: microflow Module.ACT_Delete(Target: $currentObject), buttonstyle: danger)
+actionbutton btnDelete (caption: 'Delete', action: microflow Module.ACT_Delete(Target = $currentObject), buttonstyle: danger)
 
 -- Create object and show page
 actionbutton btnNew (caption: 'New', action: create_object Module.Product then show_page Module.Product_Edit, buttonstyle: primary)
@@ -645,7 +643,7 @@ Create a menu with action items:
 
 ```sql
 navigationlist navName {
-  item itemEdit (caption: 'Edit', action: show_page Module.EditPage(entity: $EntityParameter))
+  item itemEdit (caption: 'Edit', action: show_page Module.EditPage(entity = $EntityParameter))
   item itemDelete (caption: 'Delete', action: delete)
   item itemBack (caption: 'Back', action: close_page)
 }
@@ -947,7 +945,7 @@ as an `actionbutton`'s `action:`:
 
 ```sql
 -- Rich, parameterised trigger: a card that opens the object it represents
-container tileCard (OnClick: microflow MyModule.ACT_Open(Item: $currentObject), class: 'tile') {
+container tileCard (OnClick: microflow MyModule.ACT_Open(Item = $currentObject), class: 'tile') {
   dynamictext tileValue (content: '4')
   dynamictext tileLabel (content: '4 LEFT', class: 'tile-label')
 }
@@ -1013,7 +1011,7 @@ datagrid dgMaterials (
     -- Not row-scoped: pass the selection explicitly.
     container cUnlink (
       class: 'command',
-      action: nanoflow Module.ACT_UnLink ($Material = $dgMaterials)
+      action: nanoflow Module.ACT_UnLink (Material = $dgMaterials)
     ) {
       actionbutton btnUnlink (caption: 'Unlink')
     }