Module code 

The stable diagnostic codes of mf2-syntax (mf2_model::Diagnostic::code).

A code identifies what went wrong more precisely than the mf2_model::ErrorKind. Codes are stable: a code’s meaning never changes, and a retired code is never reused. 0 means “no detail”.

Code	Kind	Meaning
1	syntax	U+0000 is not allowed anywhere in a message
2	syntax	} in text must be escaped as \}
3	syntax	\ must be followed by \, {, | or }
4	syntax	a placeholder is missing its closing }
5	syntax	a placeholder is empty ({})
6	syntax	a character that cannot appear here
7	syntax	whitespace is required here
8	syntax	a name must start here
9	syntax	= expected (option; .local declaration)
10	syntax	an option needs a value: a literal or a variable
11	syntax	an attribute’s value must be a literal
12	syntax	a quoted literal is missing its closing |
13	syntax	not a keyword (.input, .local, .match)
14	syntax	an expression {…} expected
15	syntax	.input needs a variable expression {$name …}
16	syntax	.local needs a variable $name
17	syntax	a complex message needs a body: {{…}} or .match
18	syntax	nothing may follow the body of a complex message
19	syntax	a quoted pattern is missing its closing }}
20	syntax	.match needs at least one selector $name
21	syntax	.match needs at least one variant
22	syntax	a variant needs at least one key
23	syntax	a variant needs a quoted pattern {{…}}
24	syntax	markup is not allowed in a declaration
25	syntax	an expression needs an operand or a function before attributes
26	syntax	the source is longer than u32::MAX bytes
101	variant-key-mismatch	a variant’s key count differs from the selector count
102	missing-fallback-variant	no variant has only catch-all keys
103	missing-selector-annotation	the selector does not (directly or indirectly) reference a declaration with a function
104	duplicate-declaration	the variable was declared, or used, in a previous declaration
105	duplicate-declaration	the declaration’s own expression uses the variable it binds
106	duplicate-option-name	two options of one function or markup have the same name (under NFC)
107	duplicate-variant	two variants have the same keys (under NFC)

Constants

CONTENT_AFTER_BODY

Nothing may follow the body of a complex message.

DUPLICATE_DECLARATION

The variable was declared, or used, in a previous declaration.

DUPLICATE_OPTION_NAME

Two options of one function or markup have the same name (under NFC).

DUPLICATE_VARIANT

Two variants have the same keys (under NFC).

EMPTY_PLACEHOLDER

A placeholder is empty ({}).

EXPECTED_EQUALS

= expected (option; .local declaration).

EXPECTED_EXPRESSION

An expression {…} expected.

EXPECTED_KEY

A variant needs at least one key.

EXPECTED_LITERAL

An attribute’s value must be a literal.

EXPECTED_NAME

A name must start here.

EXPECTED_OPERAND

An expression needs an operand or a function before attributes.

EXPECTED_OPTION_VALUE

An option needs a value: a literal or a variable.

EXPECTED_QUOTED_PATTERN

A variant needs a quoted pattern {{…}}.

EXPECTED_SELECTOR

.match needs at least one selector $name.

EXPECTED_VARIABLE

.local needs a variable $name.

EXPECTED_VARIABLE_EXPRESSION

.input needs a variable expression {$name …}.

EXPECTED_VARIANT

.match needs at least one variant.

INVALID_ESCAPE

\ must be followed by \, {, | or }.

MARKUP_NOT_ALLOWED

Markup is not allowed in a declaration.

MISSING_BODY

A complex message needs a body: {{…}} or .match.

MISSING_FALLBACK_VARIANT

No variant has only catch-all keys.

MISSING_SELECTOR_ANNOTATION

The selector does not (directly or indirectly) reference a declaration with a function.

MISSING_WHITESPACE

Whitespace is required here.

NUL_CHARACTER

U+0000 is not allowed anywhere in a message.

SELF_REFERENCING_DECLARATION

The declaration’s own expression uses the variable it binds.

SOURCE_TOO_LONG

The source is longer than u32::MAX bytes.

UNESCAPED_CLOSE_BRACE

} in text must be escaped as \}.

UNEXPECTED_CHARACTER

A character that cannot appear here.

UNKNOWN_KEYWORD

Not a keyword (.input, .local, .match).

UNTERMINATED_PLACEHOLDER

A placeholder is missing its closing }.

UNTERMINATED_QUOTED_LITERAL

A quoted literal is missing its closing |.

UNTERMINATED_QUOTED_PATTERN

A quoted pattern is missing its closing }}.

VARIANT_KEY_MISMATCH

A variant’s key count differs from the selector count.

Functions

describe

A one-line description of code, or None for an unknown code.