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Reference

Diagnostics

A rejected source gets exactly one diagnostic: the first problem in a fixed order of checks, with a stable kind[code]. Every page below shows a source that triggers the code and a fix, both run through ulang-lite when this site was built.

Kind	Means
`syntax`	the text is not v1 contract syntax
`limit`	a resource bound was exceeded: size, nesting, tokens, literal range, condition depth
`unsupported`	the construct parses, but is outside the executable subset
`semantic`	the contract is well formed but inconsistent: types, names, clause ids, actions, mode

`syntax`

Code	Meaning
`syntax[syntax]`	The text is not µLang v1 contract syntax.

`limit`

Code	Meaning
`limit[source-size]`	The source is empty, or larger than `maxSourceBytes` (65,536 UTF-8 bytes by default).
`limit[nesting-or-tokens]`	`{ ( [` nest deeper than `maxNesting` (20), or the source has more than `maxTokens` (6,000) words.
`limit[boolean-tokens]`	The text `AND` or `OR` occurs more than `maxBooleanOperators` (256) times.
`limit[integer-range]`	An integer literal outside ±(2^53−1).
`limit[float-range]`	A float literal that is not finite, or whose magnitude exceeds 2^53−1.
`limit[condition-depth]`	A condition tree deeper than `maxConditionDepth` (16).

`unsupported`

Code	Meaning
`unsupported[not-operator]`	The text `NOT` appears outside a string, comment or source tag.
`unsupported[arithmetic]`	`+ * / ^`, or a `-` that is not directly followed by a digit.
`unsupported[type-unsupported]`	A field or constant type other than `int`, `float`, `bool` or `string`.
`unsupported[constants-named]`	A named `CONSTANTS` block.
`unsupported[constant-form]`	A constant without a `[SOURCE:id]` tag.
`unsupported[constant-type]`	A constant whose type is not primitive, found by `checkConstants`.
`unsupported[constant-invalid]`	A soft (`=`), duplicate or badly named constant, or a value of the wrong kind or range.
`unsupported[trigger-form]`	A trigger without parentheses, or with a `WHEN` guard.
`unsupported[trigger-params]`	A trigger with parameters.
`unsupported[ensure-form]`	An `ENSURE` that is not exactly `ENSURE action() WHEN condition [SOURCE:id]`.
`unsupported[forbid-form]`	A `FORBID` with arguments, or without a condition or source tag.
`unsupported[call-or-arithmetic]`	A function call, or a subtraction such as `cap -1`, in a condition.
`unsupported[condition-form]`	A condition that is a bare operand or an assignment.
`unsupported[literal-comparison]`	A name compared with a literal, such as `cap == 25`.
`unsupported[unknown-field]`	`Entity.field` where the entity declares no such field.
`unsupported[unknown-name]`	A name that is not a declared constant.
`unsupported[foreign-reference]`	A path on another entity, or a parenthesised value.
`unsupported[kind-mismatch]`	Comparing values of different kinds, or ordering strings or booleans.
`unsupported[nonnumeric-comparison]`	A string or boolean comparison not written as `Entity.field op literal`.

`semantic`

Code	Meaning
`semantic[empty-guarantee]`	A `GUARANTEE` block with no `ENSURE` clauses.
`semantic[enforcement-mode]`	The contract is not `ENFORCEMENT_MODE: enforced`.
`semantic[context-required]`	The contract has no `CONTEXT`.
`semantic[entity]`	Not exactly one named `ENTITIES` block, or not the entity the caller expects.
`semantic[fields]`	Duplicate fields, or fields that differ from the schema the caller pinned.
`semantic[constant-collides]`	A constant has the same name as a field.
`semantic[trigger-required]`	The contract has no `TRIGGER` block.
`semantic[trigger-entry]`	A duplicate trigger action, or one the caller did not expect.
`semantic[trigger-incomplete]`	`TRIGGER` does not list exactly the actions the caller pinned.
`semantic[clause-source]`	An executable clause without a source tag, found by `validateContract`.
`semantic[clause-id]`	An invalid or duplicate clause id, `[ SOURCE:` with a space, or an action not in `TRIGGER`.
`semantic[clause-predicate]`	A clause without `WHEN`, found by `validateContract`.
`semantic[ungoverned-action]`	An action in `TRIGGER` has no clause.
`semantic[duplicate-contract]`	Two contracts with the same name in one source.