fix(mdl): refuse throw, float/currency/date and the parenthesised association; warn on unstored index names and enum-value docs

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

@@ -35,3 +35,4 @@
 {"area": "mdl/visitor", "date": "2026-09-24", "symptom": "`datagrid dg (DataSource: Mod.Car, …)` — the bare-entity shorthand — passed `check` (no project), `exec --no-check` printed \"Created page\", `describe page` showed `datagrid dg (onClick: …)` with the source gone, and mxbuild 11.14.0 reported CE0488 \"No entity configured for the data source of this widgets container\" + CE1571 + two column-attribute errors on that one grid. With `-p`, the reference pass refused it instead, but with the misleading \"Attribute 'Name' is bound but there is no enclosing data container providing entity context\" on a grid whose source the script did name.", "cause": "Every dataSourceExprV3 alternative starts with a keyword (DATABASE/MICROFLOW/…) or a VARIABLE, so `DataSource: Mod.Car` matched none and fell through to the generic `keyword COLON propertyValueV3` branch at the end of widgetPropertyV3 (DATASOURCE is in `keyword`). The visitor stored the string \"Mod.Car\"; GetDataSource() only type-asserts *ast.DataSourceV3, so nothing downstream saw it.", "file": "`mdl/visitor/visitor_page_v3.go` (bareEntityDataSource, bareEntityWidgets)", "insight": "Resolve the shorthand in the VISITOR, keyed on widget type (datagrid/listview/gallery/dataview), not as a grammar alternative. The first cut added `DATASOURCE COLON qualifiedName` to widgetPropertyV3 and broke the Barcode Scanner: a pluggable widget's generic keys are its own .mpk keys, and its `datasource: Module.Entity.Code` binds an ATTRIBUTE (Image's `datasource` is an enum) — only the widget type says what the key means. Grep `\"propertyKey\": \"datasource\"` in modelsdk/widgets/definitions before giving a common word a meaning. The tell for the class is a `map[string]any` property whose readers type-assert: a value of the wrong Go type is invisible rather than wrong. Side effects worth knowing: a data view with the shorthand (maint2-editable-never-create-page.mdl had one, unbound and unnoticed) is now refused as MDL-WIDGET09 instead of written unbound; `-p` reference checking on main already refused the grid case but blamed the column ('no enclosing data container'), a downstream symptom reading as user error; ALTER `set DataSource = M.E` was never silent (refuses 'must be a datasource expression'). Control: pre-fix binary + `exec --no-check` on a fresh 11.14.0 app reproduced the issue's four mxbuild errors verbatim; fixed binary, same script, 0 errors.", "refs": ["ako/mxcli#576", "ako/mxcli#552"], "ce": ["CE0488", "CE1571"]}
 {"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)"}

.claude/skills/mendix/generate-domain-model/reference/patterns.md

@@ -216,7 +216,7 @@ alter entity Module.Customer
 
 -- Add an index
 alter entity Module.Customer
-  add index idx_email (Email asc);
+  add index (Email asc);
 
 -- Reposition entity on domain model canvas
 alter entity Module.Customer

.claude/skills/mendix/generate-domain-model/reference/syntax.md

@@ -185,8 +185,8 @@ create persistent entity Module.EntityName (
   attributename: string(200) not null error 'Attribute name is required',
   /** Numeric value */
   Amount: decimal,
-  /** Date field */
-  CreationDate: date,
+  /** Date field (there is no date-only type) */
+  CreationDate: datetime,
   /** Boolean flag */
   IsActive: boolean not null error 'IsActive flag is required' default true,
   /** Enumeration field */

.claude/skills/mendix/mdl-entities/SKILL.md

@@ -35,7 +35,7 @@ create persistent entity Module.Customer (
   IsActive: boolean default true,
 
   -- Date/Time
-  BirthDate: date,
+  BirthDate: datetime,   -- there is no date-only type; `date` is refused
   -- Use autocreateddate (not datetime) to record when the object was created.
   -- 'CreatedDate' as a plain datetime triggers lint error MDL020.
   CreatedDate: autocreateddate,
@@ -77,7 +77,6 @@ create non-persistent entity Module.CustomerSearchParams (
 | Decimal | `Name: decimal` | `Amount: decimal` |
 | Boolean | `Name: boolean` | `IsActive: boolean` |
 | DateTime | `Name: datetime` | `CreatedAt: datetime` |
-| Date | `Name: date` | `BirthDate: date` |
 | Enumeration | `Name: Module.EnumName` | `status: Module.Status` |
 | AutoNumber | `Name: autonumber default 1` | `Code: autonumber default 1` (seed required) |
 | Binary | `Name: binary` | `FileData: binary` |
@@ -259,14 +258,17 @@ create persistent entity Module.Product (
   Category: string(50),
   Price: decimal
 )
-index idx_product_code (Code)
-index idx_product_category (Category);
+index (Code)
+index (Category);
 /
 ```
 
-> The `on` keyword is optional and reads SQL-like: `index idx_product_code on (Code)`
-> is equivalent to `index idx_product_code (Code)`. Multi-column indexes list the
-> columns in order: `index idx_pos on (Row, Col)`.
+> A Mendix index has **no name** — its columns, in order and direction, are its
+> identity. A name is accepted (`index idx_code on (Code)`) but not stored, so
+> `check` warns (MDL-IDX01), `describe` prints the index back as `index (Code)`,
+> and `drop index idx_code` cannot find it. Write indexes anonymously; drop one
+> by its columns: `alter entity Module.Product drop index (Code)`. Multi-column
+> indexes list the columns in order: `index (Row, Col desc)`.
 
 ## Complete Domain Model Example
 

cmd/mxcli/syntax/features_domain_model.go

@@ -459,7 +459,7 @@ func init() {
 			"datetime", "autonumber", "binary", "hashedstring",
 			"enumeration type", "currency", "float",
 		},
-		Syntax:  "String(n)           Variable-length text up to n characters\nInteger             Whole number (-2B to 2B)\nLong                Large whole number\nDecimal             Precise decimal for currency/calculations\nBoolean             True or false\nDateTime            Date and time combined\nDate                Date only (no time)\nAutoNumber          Auto-incrementing integer\nBinary              Binary data (files, images)\nHashedString        Securely hashed string (passwords)\nEnumeration(Name)   Reference to an enumeration\nAutoOwner           System.owner (auto-set on create)\nAutoChangedBy       System.changedBy (auto-set on commit)\nAutoCreatedDate     DateTime (auto-set on create)\nAutoChangedDate     DateTime (auto-set on commit)",
+		Syntax:  "String(n)           Variable-length text up to n characters\nInteger             Whole number (-2B to 2B)\nLong                Large whole number\nDecimal             Precise decimal for currency/calculations\nBoolean             True or false\nDateTime            Date and time combined (there is no date-only type)\nAutoNumber          Auto-incrementing integer\nBinary              Binary data (files, images)\nHashedString        Securely hashed string (passwords)\nEnumeration(Name)   Reference to an enumeration\nAutoOwner           System.owner (auto-set on create)\nAutoChangedBy       System.changedBy (auto-set on commit)\nAutoCreatedDate     DateTime (auto-set on create)\nAutoChangedDate     DateTime (auto-set on commit)\n\nNot types: Date (use DateTime), Float and Currency (use Decimal) - refused.",
 		Example: "CREATE PERSISTENT ENTITY MyModule.Customer (\n  Name: String(100) NOT NULL,\n  Age: Integer,\n  Balance: Decimal,\n  IsActive: Boolean DEFAULT true,\n  CreatedAt: DateTime,\n  Status: Enumeration(MyModule.Status)\n);",
 		SeeAlso: []string{"domain-model.entity.attributes"},
 	})

cmd/mxcli/syntax/features_microflow.go

@@ -153,7 +153,7 @@ func init() {
 
 	Register(SyntaxFeature{
 		Path:    "microflow.error-handling",
-		Summary: "Error handling with ON ERROR, THROW, CONTINUE, ROLLBACK",
+		Summary: "Error handling with ON ERROR, RAISE ERROR, CONTINUE, ROLLBACK",
 		Keywords: []string{
 			"error", "error handling", "on error", "continue",
 			"rollback", "throw", "exception", "try", "catch",
@@ -165,6 +165,10 @@ func init() {
 			"-- LOG, SHOW PAGE, CLOSE PAGE, SHOW MESSAGE, VALIDATION FEEDBACK,\n" +
 			"-- SYNCHRONIZE, DOWNLOAD FILE and the mapping/REST statements.\n" +
 			"--\n" +
+			"-- RAISE ERROR ends a handler with an error end event, re-raising the error\n" +
+			"-- being handled. There is no THROW <expr>: Mendix has no action that raises\n" +
+			"-- a new error carrying a value, and THROW is refused (it used to be dropped).\n" +
+			"--\n" +
 			"-- Two limits, both enforced rather than silently ignored:\n" +
 			"--\n" +
 			"--   ON ERROR CONTINUE is rejected by Mendix (CE6035) on CREATE, CHANGE,\n" +
@@ -180,7 +184,7 @@ func init() {
 			"-- there in EVERY form, and are refused: a nanoflow activity aborts the\n" +
 			"-- flow on error by default and has no transaction to roll back.\n" +
 			"--\n" +
-			"-- A handler that does NOT end in RETURN/THROW merges back into the main\n" +
+			"-- A handler that does NOT end in RETURN/RAISE ERROR merges back into the main\n" +
 			"-- flow, so a variable created after the merge is out of scope on the error\n" +
 			"-- path (CE0108). End the handler, or expect that.\n" +
 			"--\n" +
@@ -285,7 +289,7 @@ func init() {
 			"--               owns its own object collection and a sequence flow cannot\n" +
 			"--               leave it, so there is no graph this could build.\n" +
 			"--\n" +
-			"-- A path that has already ended (RETURN, THROW, JOIN) does NOT fall\n" +
+			"-- A path that has already ended (RETURN, RAISE ERROR, JOIN) does NOT fall\n" +
 			"-- through into a following MERGE — the merge starts a new path.",
 		Example: "CREATE MICROFLOW M.Post (Payload: String) RETURNS String\n" +
 			"BEGIN\n" +

docs-site/src/appendixes/data-type-mapping.md

@@ -122,8 +122,8 @@ CREATE PERSISTENT ENTITY Demo.AllTypes (
   /** Timestamp */
   CreatedAt: DateTime,
 
-  /** Date only */
-  BirthDate: Date,
+  /** Date of birth (Mendix has no date-only type) */
+  BirthDate: DateTime,
 
   /** File attachment */
   Attachment: Binary,

docs-site/src/language/comments.md

@@ -57,6 +57,10 @@ Documentation comments can be placed before:
 - Enumeration definitions (becomes enumeration documentation)
 - Association definitions (becomes association documentation)
 
+Not before an **enumeration value** or an **index**: Mendix stores no documentation
+on a value and no name on an index, so `check` warns that the text is not kept
+(`MDL-ENUMDOC01`, `MDL-IDX01`). Use an ordinary `--` comment for a note there.
+
 ### Updating Documentation
 
 You can also set documentation on existing entities with `ALTER ENTITY`:

docs-site/src/language/data-types.md

@@ -26,7 +26,7 @@ CREATE PERSISTENT ENTITY Demo.AllTypes (
   Amount: Decimal DEFAULT 0.00,
   IsActive: Boolean DEFAULT TRUE,
   CreatedAt: DateTime,
-  BirthDate: Date,
+  BirthDate: DateTime,
   Attachment: Binary,
   Status: Enumeration(Demo.Status) DEFAULT 'Active'
 );

docs-site/src/language/generalization.md

@@ -25,7 +25,7 @@ The most common use of generalization is creating an application-specific user e
 CREATE PERSISTENT ENTITY HR.Employee EXTENDS System.User (
   EmployeeNumber: String(20) NOT NULL UNIQUE,
   Department: String(100),
-  HireDate: Date
+  HireDate: DateTime
 );
 ```
 

docs-site/src/language/primitive-types.md

@@ -101,20 +101,15 @@ ModifiedAt: DateTime
 ScheduledFor: DateTime
 ```
 
-DateTime values include both date and time components. For date-only display, use `Date` instead.
+DateTime values include both date and time components. To show only the date, format it on the widget; there is no `Date` type.
 
-## Date
+## No `Date`, `Float` or `Currency`
 
-Date only (no time component). Internally stored as DateTime in Mendix, but the UI only shows the date portion.
-
-```sql
-Date
-```
-
-```sql
-BirthDate: Date
-ExpiryDate: Date
-```
+Mendix has no date-only attribute type: a date is a `DateTime`, and showing only
+its date part is a formatting choice on the widget. `Float` and `Currency` were
+removed in Mendix 7 in favour of `Decimal`. MDL refuses all three with the type to
+write instead — earlier versions accepted them and silently stored a `DateTime`
+(for `date`) or a `String` (for `float` and `currency`).
 
 ## AutoNumber
 

docs-site/src/reference/domain-model/create-entity.md

@@ -48,7 +48,6 @@ Each attribute definition specifies a name, a data type, and optional constraint
 | Decimal | `Decimal` | Arbitrary-precision decimal |
 | Boolean | `Boolean` | `TRUE` or `FALSE`; defaults to `FALSE` when no `DEFAULT` is given |
 | DateTime | `DateTime` | Date and time combined |
-| Date | `Date` | Date only |
 | AutoNumber | `AutoNumber` | Auto-incrementing integer (persistent entities only) |
 | Binary | `Binary` | Binary data |
 | HashedString | `HashedString` | One-way hashed string (for passwords) |
@@ -140,7 +139,7 @@ INDEX (Email);
 CREATE PERSISTENT ENTITY HR.Employee EXTENDS System.User (
     EmployeeNumber: String(20) NOT NULL UNIQUE,
     Department: String(100),
-    HireDate: Date
+    HireDate: DateTime
 );
 ```