lix/src/libexpr/nix.sdf
Eelco Dolstra ac68840e79 * Refactoring: put the Nix expression evaluator in its own library so
that it can be used by multiple programs.
2003-11-19 11:35:41 +00:00

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definition
module Main
imports Fix
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Top level syntax.
module Fix
imports Fix-Exprs Fix-Layout
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Expressions.
module Fix-Exprs
imports Fix-Lexicals URI
exports
sorts Expr Formal Bind Binds BindSemi ExprList
context-free syntax
Id -> Expr {cons("Var")}
Int -> Expr {cons("Int")}
Str -> Expr {cons("Str")}
Uri -> Expr {cons("Uri")}
Path -> Expr {cons("Path")}
"(" Expr ")" -> Expr {bracket}
Expr Expr -> Expr {cons("Call"), left}
"{" {Formal ","}* "}" ":" Expr -> Expr {cons("Function")}
Id -> Formal {cons("NoDefFormal")}
Id "?" Expr -> Formal {cons("DefFormal")}
"assert" Expr ";" Expr -> Expr {cons("Assert")}
"rec" "{" Binds "}" -> Expr {cons("Rec")}
"let" "{" Binds "}" -> Expr {cons("LetRec")}
"{" Binds "}" -> Expr {cons("Attrs")}
Id "=" Expr -> Bind {cons("Bind")}
{Bind ";"}* -> Binds
Bind ";" -> BindSemi
BindSemi* -> Binds
"[" ExprList "]" -> Expr {cons("List")}
"" -> ExprList {cons("ExprNil")}
Expr ExprList -> ExprList {cons("ExprCons")}
Expr "." Id -> Expr {cons("Select")}
"if" Expr "then" Expr "else" Expr -> Expr {cons("If")}
Expr "==" Expr -> Expr {cons("OpEq"), non-assoc}
Expr "!=" Expr -> Expr {cons("OpNEq"), non-assoc}
"!" Expr -> Expr {cons("OpNot")}
Expr "&&" Expr -> Expr {cons("OpAnd"), right}
Expr "||" Expr -> Expr {cons("OpOr"), right}
Expr "->" Expr -> Expr {cons("OpImpl"), right}
Bool -> Expr {cons("Bool")}
context-free priorities
Expr "." Id -> Expr
> Expr ExprList -> ExprList
> Expr Expr -> Expr
> "!" Expr -> Expr
> Expr "==" Expr -> Expr
> Expr "!=" Expr -> Expr
> Expr "&&" Expr -> Expr
> Expr "||" Expr -> Expr
> Expr "->" Expr -> Expr
> "assert" Expr ";" Expr -> Expr
> "{" {Formal ","}* "}" ":" Expr -> Expr
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Lexical syntax.
module Fix-Lexicals
exports
sorts Id Int Str Path PathComp Bool
lexical syntax
[a-zA-Z\_][a-zA-Z0-9\_\']* -> Id
"rec" -> Id {reject}
"let" -> Id {reject}
"if" -> Id {reject}
"then" -> Id {reject}
"else" -> Id {reject}
"true" -> Id {reject}
"false" -> Id {reject}
"assert" -> Id {reject}
[0-9]+ -> Int
"\"" ~[\n\"]* "\"" -> Str
PathComp ("/" PathComp)+ -> Path
[a-zA-Z0-9\.\_\-\+]+ -> PathComp
"true" -> Bool
"false" -> Bool
lexical restrictions
Id -/- [a-zA-Z0-9\_\']
Int -/- [0-9]
Path -/- [a-zA-Z0-9\.\_\-\+\/]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% URIs (RFC 2396, appendix A).
module URI
exports
sorts Uri Uhierpart Uopaquepart Uuricnoslash Unetpath Uabspath
Urelpath Urelsegment Uscheme Uauthority Uregname Userver
Uuserinfo Uhostport Uhost Uhostname Udomainlabel Utoplabel
UIPv4address Uport Upath Upathsegments Usegment Uparam
Upchar Uquery Ufragment Uuric Ureserved Uunreserved Umark
Uescaped Uhex Ualphanum Ualpha Ulowalpha Uupalpha Udigit
lexical syntax
Uscheme ":" (Uhierpart | Uopaquepart) -> Uri
(Unetpath | Uabspath) ("?" Uquery)? -> Uhierpart
Uuricnoslash Uuric* -> Uopaquepart
Uunreserved | Uescaped | [\;\?\:\@\&\=\+\$\,] -> Uuricnoslash
"//" Uauthority Uabspath? -> Unetpath
"/" Upathsegments -> Uabspath
"//" Uuric* -> Uabspath {reject}
Urelsegment Uabspath? -> Urelpath
(Uunreserved | Uescaped | [\;\@\&\=\+\$\,])+ -> Urelsegment
Ualpha (Ualpha | Udigit | [\+\-\.])* -> Uscheme
Userver | Uregname -> Uauthority
(Uunreserved | Uescaped | [\$\,\;\:\@\&\=\+])+ -> Uregname
((Uuserinfo "@") Uhostport) -> Userver
(Uunreserved | Uescaped | [\;\:\&\=\+\$\,])* -> Uuserinfo
Uhost (":" Uport)? -> Uhostport
Uhostname | UIPv4address -> Uhost
(Udomainlabel ".")+ Utoplabel "."? -> Uhostname
Ualphanum | Ualphanum (Ualphanum | "-")* Ualphanum -> Udomainlabel
Ualpha | Ualpha (Ualphanum | "-")* Ualphanum -> Utoplabel
Udigit+ "." Udigit+ "." Udigit+ "." Udigit+ -> UIPv4address
Udigit* -> Uport
Uabspath | Uopaquepart -> Upath
Usegment ("/" Usegment)* -> Upathsegments
Upchar* (";" Uparam)* -> Usegment
Upchar* -> Uparam
Uunreserved | Uescaped | [\:\@\&\=\+\$\,] -> Upchar
Uuric* -> Uquery
Uuric* -> Ufragment
Ureserved | Uunreserved | Uescaped -> Uuric
[\;\/\?\:\@\&\=\+\$\,] -> Ureserved
Ualphanum | Umark -> Uunreserved
[\-\_\.\!\~\*\'\(\)] -> Umark
"%" Uhex Uhex -> Uescaped
Udigit | [A-Fa-f] -> Uhex
Ualpha | Udigit -> Ualphanum
Ulowalpha | Uupalpha -> Ualpha
[a-z] -> Ulowalpha
[A-Z] -> Uupalpha
[0-9] -> Udigit
lexical restrictions
Uri -/- [a-zA-Z0-9\-\_\.\!\~\*\'\(\)]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Layout.
module Fix-Layout
exports
sorts HashComment Asterisk Comment EOF
lexical syntax
[\ \t\n] -> LAYOUT
HashComment -> LAYOUT
Comment -> LAYOUT
"#" ~[\n]* ([\n] | EOF) -> HashComment
"//" ~[\n]* ([\n] | EOF) -> HashComment
"/*" ( ~[\*] | Asterisk )* "*/" -> Comment
[\*] -> Asterisk
"" -> EOF
lexical restrictions
Asterisk -/- [\/]
EOF -/- ~[]
context-free restrictions
LAYOUT? -/- [\ \t\n] | [\#]