/* .. */ and C++ style //, and are ignored. The matching for C-style comments is non-greedy.
IDENTIFIER ::= [a-zA-Z][a-zA-Z0-9_]*
( ) [ ] { }, . =* / % + -< >@ : ;**== <= >= !==> ..== takes precedence over two = tokens.
0b), 10, or 16 (prefixed by 0x), and leading zeros are effectively ignored. It is possible to separate digit groups with an underscore for readability. It shall be a lexing error to use digits that do not fit into the base.
INTEGER ::= (0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)*
DECIMAL ::= [0-9]+(_[0-9]+)*\.[0-9]+(_[0-9]+)*
STRING ::= ("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3})
\" escape sequence being replaced with ".
.rsl They contains the user-defined type definitions and optionally user-defined warnings or checks.check They contain only user-defined warning or error messages for types declared in .rsl files.trlc They contain instances of the types (this is where your requirements go).rsl files are parsed. Then, if no errors are raised, all .check files are parsed. Finally, if no errors are raised, all .trlc files are parsed.
.trlc files, but it is recommended to not stop processing after the first error.
file_preamble ::= package_indicationpackage IDENTIFIER { import_clauseimport IDENTIFIER } package_indication ::= 'package' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_name import_clause ::= 'import' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_name
qualified_name.
.rsl file starts with a package declaration and is followed by type declarations.
rsl_file ::= file_preamblepackage_indication { import_clause } { type_declaration | check_blockchecks IDENTIFIER { { check_declaration } } }
.rsl file declares a package. Any given package name may only be declared once globally.
.rsl file, a package may not import a package that imports itself, directly or indirectly.
Boolean has two values, false and true.
Integer is a signed integer, with an implementation defined range. This range shall be at least -1000 to 1000, and this can be infinite.
Decimal is a signed rational with a power-of-ten denominator, with an implementation defined range. This range for the numerator shall be at least -1000 to 1000, and denominator is always a natural number with a range of at least 1 to 1000. Any of these ranges can be infinite (but the denominator is always non-negative).
String is a sequence of implementation defined characters. (The decision to support Unicode or not is left unspecified.) The maximum length of a String, if any, is implementation defined, but shall be at least 1000.
Markup_String is identical to a String, except for a few additional constraints on the string contents. Any value of type Markup_String is a valid instance of String, but not the other way around.
described_name ::= IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_name [ STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3})_description ]
qualified_name ::= [ IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_package_name '.' ] IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_name
type_declaration ::= enumeration_declaration | tuple_declaration | record_declaration
enumeration_declaration ::= 'enum' described_nameIDENTIFIER [ STRING ] '{' { enumeration_literal_specificationdescribed_name } '}' enumeration_literal_specification ::= described_nameIDENTIFIER [ STRING ]
enum ASIL { QM "Not safety relevant" A B C D } enum My_Boolean { yes no file_not_found }
tuple_declaration ::= 'tuple' described_nameIDENTIFIER [ STRING ] '{' field_declarationdescribed_name [ optional ] qualified_name { [ separator_declarationseparator separator_symbol ] field_declarationdescribed_name [ optional ] qualified_name } '}' field_declaration ::= described_nameIDENTIFIER [ STRING ] [ 'optional' ] qualified_name[ IDENTIFIER . ] IDENTIFIER_FIELD_TYPE separator_declaration ::= 'separator' separator_symbolIDENTIFIER | @ | : | ; separator_symbol ::= IDENTIFIER[a-zA-Z][a-zA-Z0-9_]* | '@' | ':' | ';'
1; 2; 3.)
x or b. This is resolved by giving precedence to the lexer. For example the string 0x123 should yield the hex integer 291; but the string 0 x123 or 0 x 123 will generate the tuple. It is recommended to warn when building tuples where a b or x separator follows an integer.
tuple Coordinate { x Decimal y Decimal } // allows you to write (4, 3) tuple Codebeamer_Item { item Integer separator @ version optional Integer } // allows you to write 12345@42 but also just 12345 tuple Doors_Item { module_id Integer separator : item_id Integer separator @ baseline optional Decimal } // allows you to write 0xdeadbeef: 666@1.0 or 0xC0ffee: 1234
record_declaration ::= [ inheritance_qualifierabstract | final ] 'type' described_nameIDENTIFIER [ STRING ] [ 'extends' qualified_name[ IDENTIFIER . ] IDENTIFIER_ROOT_TYPE ] '{' { component_declaration | component_freezingfreeze IDENTIFIER = value } '}' inheritance_qualifier ::= 'abstract' | 'final' component_declaration ::= described_nameIDENTIFIER [ STRING ] [ 'optional' ] qualified_name[ IDENTIFIER . ] IDENTIFIER_COMPONENT_TYPE [ array_declaration[ INTEGER .. * ] | [ INTEGER .. INTEGER ] ] array_declaration ::= '[' INTEGER(0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)*_lower '..' '*' ']' | '[' INTEGER(0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)*_lower '..' INTEGER(0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)*_upper ']' component_freezing ::= 'freeze' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_component '=' value
abstract, in which case no objects of this type may be declared. It must be extended (even if that extension is empty) before instances of that type can be declared. (Note that it is possible to have components of an abstract type.)
final, and the extension of a final type is also considered to be final (even if it is not explicitly marked as such). An extension of a final type may not contain any component declarations.
* is specified. An array instance for an array type with an upper bound shall not have more elements than its upper bound.
* as if it was that limit). This limit, if it exists, shall be greater than or equal to 1000.
abstract type Base_Requirement { summary "A short summary of the requirement." String description "The actual requirement text." String } type Requirement extends Base_Requirement { asil optional ASIL derived_from optional Requirement [1 .. *] } final type Supplier_Requirement extends Requirement { supplier_id Integer } type ACME_Requirement extends Supplier_Requirement { freeze supplier_id = 666 freeze asil = ASIL.QM }
.check file is simply a set of check blocks.
check_file ::= file_preamblepackage_indication { import_clause } { check_blockchecks IDENTIFIER { { check_declaration } } }
.rsl file.
.check file into the package .rsl file.
check_block ::= 'checks' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_record_or_tuple_name '{' { check_declaration } '}' check_declaration ::= expression ',' [ severitywarning | error | fatal ] STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3})_message [ ',' STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3})_details ] [ ',' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_component_name ] severity ::= 'warning' | 'error' | 'fatal'
.rsl files since it is not possible to specify a qualified name.
checks Requirement { len(description) < 10, warning "Description is too short", description derived_from != null or top_level == true, error "Requirement linkage incorrect", '''You must set either top_level to true or link this requirement to at least one other requirement using derived_from.''' } checks OverflowGuard { value >= -100, fatal "Value must be at least -100" value <= 100, fatal "Value must be at most 100" // These bound value, and effectively guard against integer // overflow in the below expression value ** 2 == 25, warning "Value is not 5 or -5" } checks Codebeamer_Item { item >= 1, error "CB Item must be positive", item version != null implies version >= 1, error "CB Version must be positive", version }
expression ::= relation { 'and' relation } | relation { 'or' relation } | relation [ 'xor' relation ] | relation [ 'implies' relation ] relation ::= simple_expression[ adding_operator ] term { adding_operator term } [ comparison_operator== | != | < | <= | > | >= simple_expression[ adding_operator ] term { adding_operator term } ] | simple_expression[ adding_operator ] term { adding_operator term } [ 'not' ] 'in' membership_choicesimple_expression .. simple_expression | simple_expression[ adding_operator ] term { adding_operator term } [ 'not' ] 'in' simple_expression[ adding_operator ] term { adding_operator term } membership_choice ::= simple_expression[ adding_operator ] term { adding_operator term } '..' simple_expression[ adding_operator ] term { adding_operator term } simple_expression ::= [ adding_operator+ | - ] termfactor { multiplying_operator factor } { adding_operator+ | - termfactor { multiplying_operator factor } } term ::= factorprimary [ ** primary ] | not primary | abs primary { multiplying_operator* | / | % factorprimary [ ** primary ] | not primary | abs primary } factor ::= primary [ '**' primary ] | 'not' primary | 'abs' primary primary ::= INTEGER(0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)* | DECIMAL[0-9]+(_[0-9]+)*\.[0-9]+(_[0-9]+)* | STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3}) | 'true' | 'false' | 'null' | name | '(' expression ')' | '(' quantified_expressionquantifier IDENTIFIER in IDENTIFIER => expression ')' | '(' conditional_expression ')'
-a % b is actually - (a % b). The semantics of % are carefully specified so that this does not matter. It does also mean that -a / -b is not legal and needs to be written as either -a / (-b) or even better (-a) / (-b). It is recommended that a linter warns whenever a unary minus is encountered that has a non-trivial term or factor as its operand.
checks Expression_Examples { asil != ASIL.QM, "must be safety related" len(summary) + len(description) > 10, "too short" description != null implies "potato" in description, "description must mention the best vegetable" (forall item in codebeamer_link => item > 50000), warning "cb link is suspiciously small" }
name ::= qualified_name[ IDENTIFIER . ] IDENTIFIER | name '.' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]* | name '[' expression ']' | name '(' parameter_listexpression { , expression } ')' parameter_list ::= expression { ',' expression }
qualified_name must resolve to record component or tuple field in scope, or a visible record object, or a visible enumeration type.
.) access resolves to an enumeration type, then the identifier must be a valid literal of that type. If the prefix of a dot (.) access resolves to a tuple, then the identifier must be a valid field of the type of that tuple. Any other prefix is an error.
name in an array indexing prefix (i.e. [ .. ]) must be an array type.
name in a function call must resolve to one of the builtin functions.
len is of arity 1. Its parameter must be of type String or an array type. Its return type is Integer.
startswith and endswith are of arity 2. All of their parameters must be of type String. The return type of either function is Boolean.
matches is of arity 2. Its parameters must be of type String. The return type is Boolean. The second parameter must be a valid regular expression. (It is implementation defined which regular expression language is used, but it is highly, _highly_ recommended to implement the standard POSIX regular expressions.)
matches function must be a static compile-time constant, i.e. it must not depend on the value of a record field or the value of a quantified variable.
len function computes the length of the given string or array.
startswith function returns true iff the first parameter fully contains the second parameter at its start.
endswith function returns true iff the first parameter fully contains the second parameter at its end.
matches function returns true iff the first parameter is matched by the regular expression given in the second parameter.
Integer type conversion rounds to the nearest integral, away from zero in the case of ties.
Decimal type conversion simply converts the given integer to the exact same rational.
checks Name_Examples { foo, "foo" // names the record field foo len(field) > 0, "foo" // name that is a function call potato[3] < potato[2], "foo" // name that is an array index Decimal(potato[0]) < wibble, "foo" // note that type conversion is necessary cb_link.item >= 50000, warning "cb item value is oddly low" // you can obtain a tuple's values }
comparison_operator ::= '==' | '!=' | '<' | '<=' | '>' | '>=' adding_operator ::= '+' | '-' multiplying_operator ::= '*' | '/' | '%'
"potato" in A + B may either create an error when attempting to concatenate the strings, OR it must work correctly. What you cannot do is cause undefined behaviour in the evaluation.
and, or, and implies. They first evaluate their left-hand side and proceed to evaluate the right-hand side if it could influence the final result. The semantics of these operators are the usual ones.
xor, and not. They do the usual thing.
== and != are defined for all types, as long as the types are compatible, i.e. they are the same types or one type is a (transitive) record extension of the other. The result is a Boolean.
<, <=, >=, and > are defined for pairs of integers or pairs of rationals only. The result is a Boolean.
not in and in are defined for integers and rationals only. All operands must have the same type, and the result is a Boolean.
not in and in are defined for Strings only. The result is a Boolean.
not in and in are defined for all arrays. The type of the left-hand side must match the element type of the array. The result is a Boolean.
x in a .. b has the same meaning as the Boolean expression x >= a and x <= b. (This means if a is less than b, it is not an error. Instead the result of such a test is always false.)
x not in a .. b has the same meaning as the Boolean expression x < a or x > b.
X in A is equivalent to (exists item in A => item == X). The array non-membership test X not in A is equivalent to (forall item in A => item != X).
+ is defined for integers, rationals, and strings. The binary subtraction operator - is defined for only integers and rationals.
+ is used to concatenate strings, the result is always a String, even if one or both operands if of type Markup_String. (This means the only way you can create a markup string is when you construct it at record object declaration.)
+, and the unary subtraction operator - is defined only for integers and rationals.
+ and - for integers and rationals is the usual one.
+ for strings is string concatenation.
*, / are defined for integers and rational types. The remainder operator % is defined for integers only. For any of these the result is always the same type as the operands.
* is the usual one.
/ for integers is floor division. (For example 5 / 2 is 2 and -5 / 2 is -3.)
/ for rationals is the usual one.
x % y satisfies the relation x = y*N + (x % y), for some (signed) value of N, with one of the following constraints met:
x % y is 0x % y has the same sign as y and an absolute value less than y** is defined for integers and rational bases, and returns the same type as its base. The exponent type is always an Integer.
** must be a static compile-time constant, i.e. it must not depend on the value of a record field or the value of a quantified variable. It must not be negative.
abs is defined for integers and rationals, and returns a (positive) integer or rational respectively.
not is defined for Booleans only, and returns a Boolean.
** is the usual one.
abs is the usual one.
not is the usual one.
quantified_expression ::= quantifierforall | exists IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_name 'in' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_component_name '=>' expression_PREDICATE quantifier ::= 'forall' | 'exists'
and or or expressions, however it is left unspecified if quantification is using short-circuit semantics or not. It is recommended (for sanity) to do the following:
conditional_expression ::= 'if' expression_CONDITION 'then' expression_DEPENDENT { 'elsif' expression_CONDITION 'then' expression_DEPENDENT } 'else' expression_DEPENDENT
.trlc file is simply a set of record object declarations.
trlc_file ::= file_preamblepackage_indication { import_clause } { trlc_entrysection_declaration | record_object_declaration } trlc_entry ::= section_declarationsection STRING { { trlc_entry } } | record_object_declaration
.rsl file, in which case it is declared by the package_indication in the .trlc file. Such a package is declared late. If two .trlc files declare the same package, then it is unspecified which file actually declares it.
section_declaration ::= 'section' STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3})_section_name '{' { trlc_entrysection_declaration | record_object_declaration } '}'
record_object_declaration ::= qualified_name[ IDENTIFIER . ] IDENTIFIER_RECORD_TYPE IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_object_name '{' { component_associationIDENTIFIER = value } '}' component_association ::= IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_component_name '=' value value ::= [ adding_operator+ | - ] INTEGER(0[xb])?[0-9a-fA-F]+(_[0-9a-fA-F]+)* | [ adding_operator+ | - ] DECIMAL[0-9]+(_[0-9]+)*\.[0-9]+(_[0-9]+)* | STRING("([^"\n]|(\"))*")|('{3}.*?'{3})|("{3}.*?"{3}) | qualified_name[ IDENTIFIER . ] IDENTIFIER_RECORD_OBJECT | qualified_name[ IDENTIFIER . ] IDENTIFIER_ENUM_TYPE '.' IDENTIFIER[a-zA-Z][a-zA-Z0-9_]*_enumeration_literal | '[' [ value { ',' value } ] ']' | tuple_aggregate tuple_aggregate ::= '(' value { ',' value } ')' | value { separator_symbolIDENTIFIER | @ | : | ; value }
(1, 2, 3), and a tuple with separators must use the separator syntax (e.g. 12345@42).
Foo_Bar is foobar and therefore it clashes with Foobar, F_Oobar, or Foo_B_A_R. But only at record declaration; when referring to other object you still have to use a precise match.
type that carries this information (it is safe to do that, as it is impossible to specify a record type with a field named type).Requirement Potato { description = "Hello World!" coordinate = (42.0, 666.0) derived_from_cb = [ 1234, // references codebeamer item 1234 (at head revision) 1900@42 // references codebeamer item 1900 at version 42 ] }
Markup_String allows you to inline references to TRLC record in a string. The format is limited and simple: any name or comma-separated list of names enclosed in double square brackets (i.e. [[ and ]]) is considered a reference.
Requirement Bean_Vehicle { description = "The car shall have [[WHEEL_COUNT]] wheels." } Requirement SW_Process { description = "We shall use [[TRLC, LOBSTER]] for achieving software traceability." } Constant WHEEL_COUNT { value = 3 } Tool TRLC { vendor = "BMW AG" url = "https://github.com/bmw-software-engineering/trlc/" license = License.GPL3 } Tool LOBSTER { vendor = "BMW AG" url = "https://github.com/bmw-software-engineering/lobster/" license = License.AGPL3 }
(if a then null else b) is rejected statically.
null == null is statically true.
null.
Version 1.3, 3 November 2008
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