Commit | Line | Data |
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ee7cd585 JM |
1 | Imports System |
2 | Imports System.IO | |
3 | Imports System.Collections.Generic | |
4 | Imports Mal | |
5 | Imports MalVal = Mal.types.MalVal | |
6 | Imports MalInt = Mal.types.MalInt | |
7 | Imports MalSymbol = Mal.types.MalSymbol | |
8 | Imports MalList = Mal.types.MalList | |
9 | Imports MalVector = Mal.types.MalVector | |
10 | Imports MalHashMap = Mal.types.MalHashMap | |
11 | Imports MalFunc = Mal.types.MalFunc | |
12 | ||
13 | Namespace Mal | |
aaba2493 | 14 | Class step2_eval |
ee7cd585 JM |
15 | ' read |
16 | Shared Function READ(str As String) As MalVal | |
17 | Return reader.read_str(str) | |
18 | End Function | |
19 | ||
20 | ' eval | |
21 | Shared Function eval_ast(ast As MalVal, env As Dictionary(Of String, MalVal)) As MalVal | |
22 | If TypeOf ast Is MalSymbol Then | |
23 | Dim sym As MalSymbol = DirectCast(ast, MalSymbol) | |
24 | return env.Item(sym.getName()) | |
25 | Else If TypeOf ast Is MalList Then | |
26 | Dim old_lst As MalList = DirectCast(ast, MalList) | |
27 | Dim new_lst As MalList | |
28 | If ast.list_Q() Then | |
29 | new_lst = New MalList | |
30 | Else | |
31 | new_lst = DirectCast(New MalVector, MalList) | |
32 | End If | |
33 | Dim mv As MalVal | |
34 | For Each mv in old_lst.getValue() | |
35 | new_lst.conj_BANG(EVAL(mv, env)) | |
36 | Next | |
37 | return new_lst | |
38 | Else If TypeOf ast Is MalHashMap Then | |
39 | Dim new_dict As New Dictionary(Of String, MalVal) | |
40 | Dim entry As KeyValuePair(Of String, MalVal) | |
41 | For Each entry in DirectCast(ast,MalHashMap).getValue() | |
42 | new_dict.Add(entry.Key, EVAL(DirectCast(entry.Value,MalVal), env)) | |
43 | Next | |
44 | return New MalHashMap(new_dict) | |
45 | Else | |
46 | return ast | |
47 | End If | |
48 | return ast | |
49 | End Function | |
50 | ||
51 | Shared Function EVAL(orig_ast As MalVal, env As Dictionary(Of String, MalVal)) As MalVal | |
52 | 'Console.WriteLine("EVAL: {0}", printer._pr_str(orig_ast, true)) | |
53 | If not orig_ast.list_Q() Then | |
54 | return eval_ast(orig_ast, env) | |
55 | End If | |
56 | ||
57 | ' apply list | |
58 | Dim ast As MalList = DirectCast(orig_ast, MalList) | |
59 | If ast.size() = 0 Then | |
60 | return ast | |
61 | End If | |
62 | Dim a0 As MalVal = ast(0) | |
63 | Dim el As MalList = DirectCast(eval_ast(ast, env), MalList) | |
64 | Dim f As MalFunc = DirectCast(el(0), MalFunc) | |
65 | Return f.apply(el.rest()) | |
66 | End Function | |
67 | ||
68 | ||
69 | Shared Function PRINT(exp As MalVal) As String | |
70 | return printer._pr_str(exp, TRUE) | |
71 | End Function | |
72 | ||
73 | ' repl | |
74 | Shared repl_env As Dictionary(Of String, MalVal) | |
75 | ||
76 | Shared Function REP(str As String) As String | |
77 | Return PRINT(EVAL(READ(str), repl_env)) | |
78 | End Function | |
79 | ||
80 | Shared Function add(a As MalList) As MalVal | |
81 | Return DirectCast(a.Item(0),MalInt) + DirectCast(a.Item(1),MalInt) | |
82 | End Function | |
83 | ||
84 | Shared Function minus(a As MalList) As MalVal | |
85 | Return DirectCast(a.Item(0),MalInt) - DirectCast(a.Item(1),MalInt) | |
86 | End Function | |
87 | ||
88 | Shared Function mult(a As MalList) As MalVal | |
89 | Return DirectCast(a.Item(0),MalInt) * DirectCast(a.Item(1),MalInt) | |
90 | End Function | |
91 | ||
92 | Shared Function div(a As MalList) As MalVal | |
93 | Return DirectCast(a.Item(0),MalInt) / DirectCast(a.Item(1),MalInt) | |
94 | End Function | |
95 | ||
96 | Shared Function Main As Integer | |
97 | Dim args As String() = Environment.GetCommandLineArgs() | |
98 | ||
99 | repl_env = New Dictionary(Of String, MalVal) | |
100 | repl_env.Add("+", New MalFunc(AddressOf add)) | |
101 | repl_env.Add("-", New MalFunc(AddressOf minus)) | |
102 | repl_env.Add("*", New MalFunc(AddressOf mult)) | |
103 | repl_env.Add("/", New MalFunc(AddressOf div)) | |
104 | ||
105 | ||
106 | If args.Length > 1 AndAlso args(1) = "--raw" Then | |
107 | Mal.readline.SetMode(Mal.readline.Modes.Raw) | |
108 | End If | |
109 | ||
110 | ' repl loop | |
111 | Dim line As String | |
112 | Do | |
113 | Try | |
114 | line = Mal.readline.Readline("user> ") | |
115 | If line is Nothing Then | |
116 | Exit Do | |
117 | End If | |
118 | If line = "" Then | |
119 | Continue Do | |
120 | End If | |
121 | Catch e As IOException | |
122 | Console.WriteLine("IOException: " & e.Message) | |
123 | End Try | |
124 | Try | |
125 | Console.WriteLine(REP(line)) | |
126 | Catch e as Exception | |
127 | Console.WriteLine("Error: " & e.Message) | |
128 | Console.WriteLine(e.StackTrace) | |
129 | Continue Do | |
130 | End Try | |
131 | Loop While True | |
132 | End function | |
aaba2493 | 133 | End Class |
ee7cd585 | 134 | End Namespace |