1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
|
definition
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Top level syntax.
module Nix
imports Nix-Exprs Nix-Layout
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Expressions.
module Nix-Exprs
imports Nix-Lexicals
exports
sorts Expr Formal Bind ExprList
context-free start-symbols Expr
context-free syntax
Id | Int | Str | Uri | Path -> Expr {cons("Var")}
"(" Expr ")" -> Expr {bracket}
Expr Expr -> Expr {cons("Call"), left}
Id ":" Expr -> Expr {cons("Function1")}
"{" {Formal ","}* "}" ":" Expr -> Expr {cons("Function")}
Id -> Formal {cons("NoDefFormal")}
Id "?" Expr -> Formal {cons("DefFormal")}
"assert" Expr ";" Expr -> Expr {cons("Assert")}
"with" Expr ";" Expr -> Expr {cons("With")}
"rec" "{" Bind* "}" -> Expr {cons("Rec")}
"let" "{" Bind* "}" -> Expr {cons("LetRec")}
"{" Bind* "}" -> Expr {cons("Attrs")}
Id "=" Expr ";" -> Bind {cons("Bind")}
"inherit" ("(" Expr ")")? Id* ";" -> Bind {cons("Inherit")}
"[" 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}
Expr "//" Expr -> Expr {cons("OpUpdate"), right}
Expr "~" Expr -> Expr {cons("SubPath"), non-assoc}
Expr "?" Id -> Expr {cons("OpHasAttr")}
Expr "+" Expr -> Expr {cons("OpPlus"), left}
context-free priorities
Expr "." Id -> Expr
> Expr ExprList -> ExprList
> Expr Expr -> Expr
> Expr "~" Expr -> Expr
> Expr "?" Id -> Expr
> Expr "+" Expr -> Expr
> "!" Expr -> Expr
> Expr "//" Expr -> Expr
> Expr "==" Expr -> Expr
> Expr "!=" Expr -> Expr
> Expr "&&" Expr -> Expr
> Expr "||" Expr -> Expr
> Expr "->" Expr -> Expr
> "if" Expr "then" Expr "else" Expr -> Expr
> "assert" Expr ";" Expr -> Expr
> "with" Expr ";" Expr -> Expr
> Id ":" Expr -> Expr
> "{" {Formal ","}* "}" ":" Expr -> Expr
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Lexical syntax.
module Nix-Lexicals
exports
sorts Id Int Str Path Uri
lexical syntax
[a-zA-Z\_][a-zA-Z0-9\_\']* -> Id
"rec" | "let" | "if" | "then" | "else" | "assert" | "with" | "inherit" -> Id {reject}
[0-9]+ -> Int
"\"" ~[\n\"]* "\"" -> Str
[a-zA-Z0-9\.\_\-\+]* ("/"[a-zA-Z0-9\.\_\-\+]+)+ -> Path
[a-zA-Z] [a-zA-Z0-9\+\-\.]* ":" [a-zA-Z0-9\%\/\?\:\@\&\=\+\$\,\-\_\.\!\~\*\']* -> Uri
lexical restrictions
Id -/- [a-zA-Z0-9\_\']
Int -/- [0-9]
Path -/- [a-zA-Z0-9\.\_\-\+\/]
Uri -/- [a-zA-Z0-9\%\/\?\:\@\&\=\+\$\,\-\_\.\!\~\*\']
"rec" "let" "if" "then" "else" "assert" "with" "inherit" -/- [A-Za-z0-9\_\']
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Layout.
module Nix-Layout
exports
sorts HashComment Asterisk Comment
lexical syntax
[\ \t\n] -> LAYOUT
HashComment -> LAYOUT
Comment -> LAYOUT
"#" ~[\n]* -> HashComment
"/*" ( ~[\*] | Asterisk )* "*/" -> Comment
[\*] ~[\/] -> Asterisk
lexical restrictions
HashComment -/- ~[\n]
context-free restrictions
LAYOUT? -/- [\ \t\n]
|