blob: 924f8b912f771e4792536148ad84388a8a74b9e8 (
plain)
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
|
#ifndef __NIXEXPR_H
#define __NIXEXPR_H
#include <map>
#include <aterm2.h>
#include "util.hh"
/* Nix expressions are represented as ATerms. The maximal sharing
property of the ATerm library allows us to implement caching of
normals forms efficiently. */
typedef ATerm Expr;
/* Mappings from ATerms to ATerms. This is just a wrapper around
ATerm tables. */
class ATermMap
{
private:
unsigned int maxLoadPct;
ATermTable table;
public:
ATermMap(unsigned int initialSize = 64, unsigned int maxLoadPct = 75);
ATermMap(const ATermMap & map);
~ATermMap();
void set(ATerm key, ATerm value);
void set(const string & key, ATerm value);
ATerm get(ATerm key) const;
ATerm get(const string & key) const;
void remove(ATerm key);
void remove(const string & key);
ATermList keys() const;
void add(const ATermMap & map);
void reset();
private:
void add(const ATermMap & map, ATermList & keys);
};
/* Convert a string to an ATerm (i.e., a quoted nullary function
applicaton). */
ATerm string2ATerm(const string & s);
string aterm2String(ATerm t);
/* Generic bottomup traversal over ATerms. The traversal first
recursively descends into subterms, and then applies the given term
function to the resulting term. */
struct TermFun
{
virtual ATerm operator () (ATerm e) = 0;
};
ATerm bottomupRewrite(TermFun & f, ATerm e);
/* Query all attributes in an attribute set expression. The
expression must be in normal form. */
void queryAllAttrs(Expr e, ATermMap & attrs);
/* Query a specific attribute from an attribute set expression. The
expression must be in normal form. */
Expr queryAttr(Expr e, const string & name);
/* Create an attribute set expression from an Attrs value. */
Expr makeAttrs(const ATermMap & attrs);
/* Perform a set of substitutions on an expression. */
Expr substitute(const ATermMap & subs, Expr e);
/* Check whether all variables are defined in the given expression.
Throw an exception if this isn't the case. */
void checkVarDefs(const ATermMap & def, Expr e);
/* Create an expression representing a boolean. */
Expr makeBool(bool b);
#endif /* !__NIXEXPR_H */
|
