root / htools / Ganeti / THH.hs @ 7eda951b
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1 | e9aaa3c6 | Iustin Pop | {-# LANGUAGE TemplateHaskell, QuasiQuotes #-} |
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2 | e9aaa3c6 | Iustin Pop | |
3 | e9aaa3c6 | Iustin Pop | {-| TemplateHaskell helper for HTools. |
4 | e9aaa3c6 | Iustin Pop | |
5 | e9aaa3c6 | Iustin Pop | As TemplateHaskell require that splices be defined in a separate |
6 | e9aaa3c6 | Iustin Pop | module, we combine all the TemplateHaskell functionality that HTools |
7 | e9aaa3c6 | Iustin Pop | needs in this module (except the one for unittests). |
8 | e9aaa3c6 | Iustin Pop | |
9 | e9aaa3c6 | Iustin Pop | -} |
10 | e9aaa3c6 | Iustin Pop | |
11 | e9aaa3c6 | Iustin Pop | {- |
12 | e9aaa3c6 | Iustin Pop | |
13 | e9aaa3c6 | Iustin Pop | Copyright (C) 2011 Google Inc. |
14 | e9aaa3c6 | Iustin Pop | |
15 | e9aaa3c6 | Iustin Pop | This program is free software; you can redistribute it and/or modify |
16 | e9aaa3c6 | Iustin Pop | it under the terms of the GNU General Public License as published by |
17 | e9aaa3c6 | Iustin Pop | the Free Software Foundation; either version 2 of the License, or |
18 | e9aaa3c6 | Iustin Pop | (at your option) any later version. |
19 | e9aaa3c6 | Iustin Pop | |
20 | e9aaa3c6 | Iustin Pop | This program is distributed in the hope that it will be useful, but |
21 | e9aaa3c6 | Iustin Pop | WITHOUT ANY WARRANTY; without even the implied warranty of |
22 | e9aaa3c6 | Iustin Pop | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
23 | e9aaa3c6 | Iustin Pop | General Public License for more details. |
24 | e9aaa3c6 | Iustin Pop | |
25 | e9aaa3c6 | Iustin Pop | You should have received a copy of the GNU General Public License |
26 | e9aaa3c6 | Iustin Pop | along with this program; if not, write to the Free Software |
27 | e9aaa3c6 | Iustin Pop | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
28 | e9aaa3c6 | Iustin Pop | 02110-1301, USA. |
29 | e9aaa3c6 | Iustin Pop | |
30 | e9aaa3c6 | Iustin Pop | -} |
31 | e9aaa3c6 | Iustin Pop | |
32 | b20cbf06 | Iustin Pop | module Ganeti.THH ( declareSADT |
33 | e9aaa3c6 | Iustin Pop | , makeJSONInstance |
34 | 6111e296 | Iustin Pop | , genOpID |
35 | 12c19659 | Iustin Pop | , genOpCode |
36 | 12c19659 | Iustin Pop | , noDefault |
37 | a0090487 | Agata Murawska | , genStrOfOp |
38 | a0090487 | Agata Murawska | , genStrOfKey |
39 | a0090487 | Agata Murawska | , genLuxiOp |
40 | e9aaa3c6 | Iustin Pop | ) where |
41 | e9aaa3c6 | Iustin Pop | |
42 | 60de49c3 | Iustin Pop | import Control.Monad (liftM, liftM2) |
43 | e9aaa3c6 | Iustin Pop | import Data.Char |
44 | 6111e296 | Iustin Pop | import Data.List |
45 | e9aaa3c6 | Iustin Pop | import Language.Haskell.TH |
46 | e9aaa3c6 | Iustin Pop | |
47 | e9aaa3c6 | Iustin Pop | import qualified Text.JSON as JSON |
48 | e9aaa3c6 | Iustin Pop | |
49 | 53664e15 | Iustin Pop | -- * Helper functions |
50 | 53664e15 | Iustin Pop | |
51 | e9aaa3c6 | Iustin Pop | -- | Ensure first letter is lowercase. |
52 | e9aaa3c6 | Iustin Pop | -- |
53 | e9aaa3c6 | Iustin Pop | -- Used to convert type name to function prefix, e.g. in @data Aa -> |
54 | e9aaa3c6 | Iustin Pop | -- aaToString@. |
55 | e9aaa3c6 | Iustin Pop | ensureLower :: String -> String |
56 | e9aaa3c6 | Iustin Pop | ensureLower [] = [] |
57 | e9aaa3c6 | Iustin Pop | ensureLower (x:xs) = toLower x:xs |
58 | e9aaa3c6 | Iustin Pop | |
59 | 53664e15 | Iustin Pop | -- | Helper for quoted expressions. |
60 | 53664e15 | Iustin Pop | varNameE :: String -> Q Exp |
61 | 53664e15 | Iustin Pop | varNameE = varE . mkName |
62 | 53664e15 | Iustin Pop | |
63 | 53664e15 | Iustin Pop | -- | showJSON as an expression, for reuse. |
64 | 53664e15 | Iustin Pop | showJSONE :: Q Exp |
65 | 53664e15 | Iustin Pop | showJSONE = varNameE "showJSON" |
66 | 53664e15 | Iustin Pop | |
67 | e9aaa3c6 | Iustin Pop | -- | ToString function name. |
68 | e9aaa3c6 | Iustin Pop | toStrName :: String -> Name |
69 | e9aaa3c6 | Iustin Pop | toStrName = mkName . (++ "ToString") . ensureLower |
70 | e9aaa3c6 | Iustin Pop | |
71 | e9aaa3c6 | Iustin Pop | -- | FromString function name. |
72 | e9aaa3c6 | Iustin Pop | fromStrName :: String -> Name |
73 | e9aaa3c6 | Iustin Pop | fromStrName = mkName . (++ "FromString") . ensureLower |
74 | e9aaa3c6 | Iustin Pop | |
75 | 6111e296 | Iustin Pop | -- | Converts a name to it's varE/litE representations. |
76 | 6111e296 | Iustin Pop | -- |
77 | 6111e296 | Iustin Pop | reprE :: Either String Name -> Q Exp |
78 | 53664e15 | Iustin Pop | reprE = either stringE varE |
79 | 53664e15 | Iustin Pop | |
80 | 60de49c3 | Iustin Pop | -- | Smarter function application. |
81 | 60de49c3 | Iustin Pop | -- |
82 | 60de49c3 | Iustin Pop | -- This does simply f x, except that if is 'id', it will skip it, in |
83 | 60de49c3 | Iustin Pop | -- order to generate more readable code when using -ddump-splices. |
84 | 60de49c3 | Iustin Pop | appFn :: Exp -> Exp -> Exp |
85 | 60de49c3 | Iustin Pop | appFn f x | f == VarE 'id = x |
86 | 60de49c3 | Iustin Pop | | otherwise = AppE f x |
87 | 60de49c3 | Iustin Pop | |
88 | 53664e15 | Iustin Pop | -- * Template code for simple string-equivalent ADTs |
89 | 6111e296 | Iustin Pop | |
90 | e9aaa3c6 | Iustin Pop | -- | Generates a data type declaration. |
91 | e9aaa3c6 | Iustin Pop | -- |
92 | e9aaa3c6 | Iustin Pop | -- The type will have a fixed list of instances. |
93 | e9aaa3c6 | Iustin Pop | strADTDecl :: Name -> [String] -> Dec |
94 | e9aaa3c6 | Iustin Pop | strADTDecl name constructors = |
95 | e9aaa3c6 | Iustin Pop | DataD [] name [] |
96 | e9aaa3c6 | Iustin Pop | (map (flip NormalC [] . mkName) constructors) |
97 | e9aaa3c6 | Iustin Pop | [''Show, ''Read, ''Eq, ''Enum, ''Bounded, ''Ord] |
98 | e9aaa3c6 | Iustin Pop | |
99 | e9aaa3c6 | Iustin Pop | -- | Generates a toString function. |
100 | e9aaa3c6 | Iustin Pop | -- |
101 | e9aaa3c6 | Iustin Pop | -- This generates a simple function of the form: |
102 | e9aaa3c6 | Iustin Pop | -- |
103 | e9aaa3c6 | Iustin Pop | -- @ |
104 | e9aaa3c6 | Iustin Pop | -- nameToString :: Name -> String |
105 | e9aaa3c6 | Iustin Pop | -- nameToString Cons1 = var1 |
106 | e9aaa3c6 | Iustin Pop | -- nameToString Cons2 = \"value2\" |
107 | e9aaa3c6 | Iustin Pop | -- @ |
108 | 6111e296 | Iustin Pop | genToString :: Name -> Name -> [(String, Either String Name)] -> Q [Dec] |
109 | e9aaa3c6 | Iustin Pop | genToString fname tname constructors = do |
110 | e9aaa3c6 | Iustin Pop | sigt <- [t| $(conT tname) -> String |] |
111 | e9aaa3c6 | Iustin Pop | -- the body clauses, matching on the constructor and returning the |
112 | e9aaa3c6 | Iustin Pop | -- string value |
113 | e9aaa3c6 | Iustin Pop | clauses <- mapM (\(c, v) -> clause [recP (mkName c) []] |
114 | 6111e296 | Iustin Pop | (normalB (reprE v)) []) constructors |
115 | e9aaa3c6 | Iustin Pop | return [SigD fname sigt, FunD fname clauses] |
116 | e9aaa3c6 | Iustin Pop | |
117 | e9aaa3c6 | Iustin Pop | -- | Generates a fromString function. |
118 | e9aaa3c6 | Iustin Pop | -- |
119 | e9aaa3c6 | Iustin Pop | -- The function generated is monadic and can fail parsing the |
120 | e9aaa3c6 | Iustin Pop | -- string. It is of the form: |
121 | e9aaa3c6 | Iustin Pop | -- |
122 | e9aaa3c6 | Iustin Pop | -- @ |
123 | e9aaa3c6 | Iustin Pop | -- nameFromString :: (Monad m) => String -> m Name |
124 | e9aaa3c6 | Iustin Pop | -- nameFromString s | s == var1 = Cons1 |
125 | e9aaa3c6 | Iustin Pop | -- | s == \"value2\" = Cons2 |
126 | e9aaa3c6 | Iustin Pop | -- | otherwise = fail /.../ |
127 | e9aaa3c6 | Iustin Pop | -- @ |
128 | e9aaa3c6 | Iustin Pop | genFromString :: Name -> Name -> [(String, Name)] -> Q [Dec] |
129 | e9aaa3c6 | Iustin Pop | genFromString fname tname constructors = do |
130 | e9aaa3c6 | Iustin Pop | -- signature of form (Monad m) => String -> m $name |
131 | e9aaa3c6 | Iustin Pop | sigt <- [t| (Monad m) => String -> m $(conT tname) |] |
132 | e9aaa3c6 | Iustin Pop | -- clauses for a guarded pattern |
133 | e9aaa3c6 | Iustin Pop | let varp = mkName "s" |
134 | e9aaa3c6 | Iustin Pop | varpe = varE varp |
135 | e9aaa3c6 | Iustin Pop | clauses <- mapM (\(c, v) -> do |
136 | e9aaa3c6 | Iustin Pop | -- the clause match condition |
137 | e9aaa3c6 | Iustin Pop | g <- normalG [| $varpe == $(varE v) |] |
138 | e9aaa3c6 | Iustin Pop | -- the clause result |
139 | e9aaa3c6 | Iustin Pop | r <- [| return $(conE (mkName c)) |] |
140 | e9aaa3c6 | Iustin Pop | return (g, r)) constructors |
141 | e9aaa3c6 | Iustin Pop | -- the otherwise clause (fallback) |
142 | e9aaa3c6 | Iustin Pop | oth_clause <- do |
143 | e9aaa3c6 | Iustin Pop | g <- normalG [| otherwise |] |
144 | e9aaa3c6 | Iustin Pop | r <- [|fail ("Invalid string value for type " ++ |
145 | e9aaa3c6 | Iustin Pop | $(litE (stringL (nameBase tname))) ++ ": " ++ $varpe) |] |
146 | e9aaa3c6 | Iustin Pop | return (g, r) |
147 | e9aaa3c6 | Iustin Pop | let fun = FunD fname [Clause [VarP varp] |
148 | e9aaa3c6 | Iustin Pop | (GuardedB (clauses++[oth_clause])) []] |
149 | e9aaa3c6 | Iustin Pop | return [SigD fname sigt, fun] |
150 | e9aaa3c6 | Iustin Pop | |
151 | e9aaa3c6 | Iustin Pop | -- | Generates a data type from a given string format. |
152 | e9aaa3c6 | Iustin Pop | -- |
153 | e9aaa3c6 | Iustin Pop | -- The format is expected to multiline. The first line contains the |
154 | e9aaa3c6 | Iustin Pop | -- type name, and the rest of the lines must contain two words: the |
155 | e9aaa3c6 | Iustin Pop | -- constructor name and then the string representation of the |
156 | e9aaa3c6 | Iustin Pop | -- respective constructor. |
157 | e9aaa3c6 | Iustin Pop | -- |
158 | e9aaa3c6 | Iustin Pop | -- The function will generate the data type declaration, and then two |
159 | e9aaa3c6 | Iustin Pop | -- functions: |
160 | e9aaa3c6 | Iustin Pop | -- |
161 | e9aaa3c6 | Iustin Pop | -- * /name/ToString, which converts the type to a string |
162 | e9aaa3c6 | Iustin Pop | -- |
163 | e9aaa3c6 | Iustin Pop | -- * /name/FromString, which (monadically) converts from a string to the type |
164 | e9aaa3c6 | Iustin Pop | -- |
165 | e9aaa3c6 | Iustin Pop | -- Note that this is basically just a custom show/read instance, |
166 | e9aaa3c6 | Iustin Pop | -- nothing else. |
167 | e9aaa3c6 | Iustin Pop | declareSADT :: String -> [(String, Name)] -> Q [Dec] |
168 | e9aaa3c6 | Iustin Pop | declareSADT sname cons = do |
169 | e9aaa3c6 | Iustin Pop | let name = mkName sname |
170 | e9aaa3c6 | Iustin Pop | ddecl = strADTDecl name (map fst cons) |
171 | 6111e296 | Iustin Pop | -- process cons in the format expected by genToString |
172 | 6111e296 | Iustin Pop | cons' = map (\(a, b) -> (a, Right b)) cons |
173 | 6111e296 | Iustin Pop | tostr <- genToString (toStrName sname) name cons' |
174 | e9aaa3c6 | Iustin Pop | fromstr <- genFromString (fromStrName sname) name cons |
175 | e9aaa3c6 | Iustin Pop | return $ ddecl:tostr ++ fromstr |
176 | e9aaa3c6 | Iustin Pop | |
177 | e9aaa3c6 | Iustin Pop | |
178 | e9aaa3c6 | Iustin Pop | -- | Creates the showJSON member of a JSON instance declaration. |
179 | e9aaa3c6 | Iustin Pop | -- |
180 | e9aaa3c6 | Iustin Pop | -- This will create what is the equivalent of: |
181 | e9aaa3c6 | Iustin Pop | -- |
182 | e9aaa3c6 | Iustin Pop | -- @ |
183 | e9aaa3c6 | Iustin Pop | -- showJSON = showJSON . /name/ToString |
184 | e9aaa3c6 | Iustin Pop | -- @ |
185 | e9aaa3c6 | Iustin Pop | -- |
186 | e9aaa3c6 | Iustin Pop | -- in an instance JSON /name/ declaration |
187 | e9aaa3c6 | Iustin Pop | genShowJSON :: String -> Q [Dec] |
188 | e9aaa3c6 | Iustin Pop | genShowJSON name = [d| showJSON = JSON.showJSON . $(varE (toStrName name)) |] |
189 | e9aaa3c6 | Iustin Pop | |
190 | e9aaa3c6 | Iustin Pop | -- | Creates the readJSON member of a JSON instance declaration. |
191 | e9aaa3c6 | Iustin Pop | -- |
192 | e9aaa3c6 | Iustin Pop | -- This will create what is the equivalent of: |
193 | e9aaa3c6 | Iustin Pop | -- |
194 | e9aaa3c6 | Iustin Pop | -- @ |
195 | e9aaa3c6 | Iustin Pop | -- readJSON s = case readJSON s of |
196 | e9aaa3c6 | Iustin Pop | -- Ok s' -> /name/FromString s' |
197 | e9aaa3c6 | Iustin Pop | -- Error e -> Error /description/ |
198 | e9aaa3c6 | Iustin Pop | -- @ |
199 | e9aaa3c6 | Iustin Pop | -- |
200 | e9aaa3c6 | Iustin Pop | -- in an instance JSON /name/ declaration |
201 | e9aaa3c6 | Iustin Pop | genReadJSON :: String -> Q Dec |
202 | e9aaa3c6 | Iustin Pop | genReadJSON name = do |
203 | e9aaa3c6 | Iustin Pop | let s = mkName "s" |
204 | e9aaa3c6 | Iustin Pop | body <- [| case JSON.readJSON $(varE s) of |
205 | e9aaa3c6 | Iustin Pop | JSON.Ok s' -> $(varE (fromStrName name)) s' |
206 | e9aaa3c6 | Iustin Pop | JSON.Error e -> |
207 | e9aaa3c6 | Iustin Pop | JSON.Error $ "Can't parse string value for type " ++ |
208 | 53664e15 | Iustin Pop | $(stringE name) ++ ": " ++ e |
209 | e9aaa3c6 | Iustin Pop | |] |
210 | e9aaa3c6 | Iustin Pop | return $ FunD (mkName "readJSON") [Clause [VarP s] (NormalB body) []] |
211 | e9aaa3c6 | Iustin Pop | |
212 | e9aaa3c6 | Iustin Pop | -- | Generates a JSON instance for a given type. |
213 | e9aaa3c6 | Iustin Pop | -- |
214 | e9aaa3c6 | Iustin Pop | -- This assumes that the /name/ToString and /name/FromString functions |
215 | e9aaa3c6 | Iustin Pop | -- have been defined as by the 'declareSADT' function. |
216 | e9aaa3c6 | Iustin Pop | makeJSONInstance :: Name -> Q [Dec] |
217 | e9aaa3c6 | Iustin Pop | makeJSONInstance name = do |
218 | e9aaa3c6 | Iustin Pop | let base = nameBase name |
219 | e9aaa3c6 | Iustin Pop | showJ <- genShowJSON base |
220 | e9aaa3c6 | Iustin Pop | readJ <- genReadJSON base |
221 | e9aaa3c6 | Iustin Pop | return [InstanceD [] (AppT (ConT ''JSON.JSON) (ConT name)) (readJ:showJ)] |
222 | 6111e296 | Iustin Pop | |
223 | 53664e15 | Iustin Pop | -- * Template code for opcodes |
224 | 53664e15 | Iustin Pop | |
225 | 6111e296 | Iustin Pop | -- | Transforms a CamelCase string into an_underscore_based_one. |
226 | 6111e296 | Iustin Pop | deCamelCase :: String -> String |
227 | 6111e296 | Iustin Pop | deCamelCase = |
228 | 6111e296 | Iustin Pop | intercalate "_" . map (map toUpper) . groupBy (\_ b -> not $ isUpper b) |
229 | 6111e296 | Iustin Pop | |
230 | 05ff7a00 | Agata Murawska | -- | Computes the name of a given constructor. |
231 | 6111e296 | Iustin Pop | constructorName :: Con -> Q Name |
232 | 6111e296 | Iustin Pop | constructorName (NormalC name _) = return name |
233 | 6111e296 | Iustin Pop | constructorName (RecC name _) = return name |
234 | 6111e296 | Iustin Pop | constructorName x = fail $ "Unhandled constructor " ++ show x |
235 | 6111e296 | Iustin Pop | |
236 | a0090487 | Agata Murawska | -- | Builds the generic constructor-to-string function. |
237 | 6111e296 | Iustin Pop | -- |
238 | 6111e296 | Iustin Pop | -- This generates a simple function of the following form: |
239 | 6111e296 | Iustin Pop | -- |
240 | 6111e296 | Iustin Pop | -- @ |
241 | a0090487 | Agata Murawska | -- fname (ConStructorOne {}) = trans_fun("ConStructorOne") |
242 | a0090487 | Agata Murawska | -- fname (ConStructorTwo {}) = trans_fun("ConStructorTwo") |
243 | 6111e296 | Iustin Pop | -- @ |
244 | 6111e296 | Iustin Pop | -- |
245 | 6111e296 | Iustin Pop | -- This builds a custom list of name/string pairs and then uses |
246 | 6111e296 | Iustin Pop | -- 'genToString' to actually generate the function |
247 | a0090487 | Agata Murawska | genConstrToStr :: (String -> String) -> Name -> String -> Q [Dec] |
248 | a0090487 | Agata Murawska | genConstrToStr trans_fun name fname = do |
249 | 6111e296 | Iustin Pop | TyConI (DataD _ _ _ cons _) <- reify name |
250 | 6111e296 | Iustin Pop | cnames <- mapM (liftM nameBase . constructorName) cons |
251 | a0090487 | Agata Murawska | let svalues = map (Left . trans_fun) cnames |
252 | 6111e296 | Iustin Pop | genToString (mkName fname) name $ zip cnames svalues |
253 | 12c19659 | Iustin Pop | |
254 | a0090487 | Agata Murawska | -- | Constructor-to-string for OpCode. |
255 | a0090487 | Agata Murawska | genOpID :: Name -> String -> Q [Dec] |
256 | a0090487 | Agata Murawska | genOpID = genConstrToStr deCamelCase |
257 | 12c19659 | Iustin Pop | |
258 | 05ff7a00 | Agata Murawska | -- | OpCode parameter (field) type. |
259 | 12c19659 | Iustin Pop | type OpParam = (String, Q Type, Q Exp) |
260 | 12c19659 | Iustin Pop | |
261 | 12c19659 | Iustin Pop | -- | Generates the OpCode data type. |
262 | 12c19659 | Iustin Pop | -- |
263 | 12c19659 | Iustin Pop | -- This takes an opcode logical definition, and builds both the |
264 | 12c19659 | Iustin Pop | -- datatype and the JSON serialisation out of it. We can't use a |
265 | 12c19659 | Iustin Pop | -- generic serialisation since we need to be compatible with Ganeti's |
266 | 12c19659 | Iustin Pop | -- own, so we have a few quirks to work around. |
267 | 12c19659 | Iustin Pop | -- |
268 | 12c19659 | Iustin Pop | -- There are three things to be defined for each parameter: |
269 | 12c19659 | Iustin Pop | -- |
270 | 12c19659 | Iustin Pop | -- * name |
271 | 12c19659 | Iustin Pop | -- |
272 | 12c19659 | Iustin Pop | -- * type; if this is 'Maybe', will only be serialised if it's a |
273 | 12c19659 | Iustin Pop | -- 'Just' value |
274 | 12c19659 | Iustin Pop | -- |
275 | 12c19659 | Iustin Pop | -- * default; if missing, won't raise an exception, but will instead |
276 | 12c19659 | Iustin Pop | -- use the default |
277 | 12c19659 | Iustin Pop | -- |
278 | 12c19659 | Iustin Pop | genOpCode :: String -- ^ Type name to use |
279 | 12c19659 | Iustin Pop | -> [(String, [OpParam])] -- ^ Constructor name and parameters |
280 | 12c19659 | Iustin Pop | -> Q [Dec] |
281 | 12c19659 | Iustin Pop | genOpCode name cons = do |
282 | 12c19659 | Iustin Pop | decl_d <- mapM (\(cname, fields) -> do |
283 | 12c19659 | Iustin Pop | -- we only need the type of the field, without Q |
284 | 12c19659 | Iustin Pop | fields' <- mapM (\(_, qt, _) -> |
285 | 12c19659 | Iustin Pop | qt >>= \t -> return (NotStrict, t)) |
286 | 12c19659 | Iustin Pop | fields |
287 | 12c19659 | Iustin Pop | return $ NormalC (mkName cname) fields') |
288 | 12c19659 | Iustin Pop | cons |
289 | 12c19659 | Iustin Pop | let declD = DataD [] (mkName name) [] decl_d [''Show, ''Read, ''Eq] |
290 | 12c19659 | Iustin Pop | |
291 | 12c19659 | Iustin Pop | (savesig, savefn) <- genSaveOpCode cons |
292 | 12c19659 | Iustin Pop | (loadsig, loadfn) <- genLoadOpCode cons |
293 | 12c19659 | Iustin Pop | return [declD, loadsig, loadfn, savesig, savefn] |
294 | 12c19659 | Iustin Pop | |
295 | 05ff7a00 | Agata Murawska | -- | Checks whether a given parameter is options. |
296 | 12c19659 | Iustin Pop | -- |
297 | 12c19659 | Iustin Pop | -- This requires that it's a 'Maybe'. |
298 | 12c19659 | Iustin Pop | isOptional :: Type -> Bool |
299 | 12c19659 | Iustin Pop | isOptional (AppT (ConT dt) _) | dt == ''Maybe = True |
300 | 12c19659 | Iustin Pop | isOptional _ = False |
301 | 12c19659 | Iustin Pop | |
302 | 12c19659 | Iustin Pop | -- | Generates the \"save\" expression for a single opcode parameter. |
303 | 12c19659 | Iustin Pop | -- |
304 | 12c19659 | Iustin Pop | -- There is only one special handling mode: if the parameter is of |
305 | 12c19659 | Iustin Pop | -- 'Maybe' type, then we only save it if it's a 'Just' value, |
306 | 12c19659 | Iustin Pop | -- otherwise we skip it. |
307 | 12c19659 | Iustin Pop | saveField :: Name -- ^ The name of variable that contains the value |
308 | 12c19659 | Iustin Pop | -> OpParam -- ^ Parameter definition |
309 | 12c19659 | Iustin Pop | -> Q Exp |
310 | 12c19659 | Iustin Pop | saveField fvar (fname, qt, _) = do |
311 | 12c19659 | Iustin Pop | t <- qt |
312 | 53664e15 | Iustin Pop | let fnexp = stringE fname |
313 | 12c19659 | Iustin Pop | fvare = varE fvar |
314 | 12c19659 | Iustin Pop | (if isOptional t |
315 | 12c19659 | Iustin Pop | then [| case $fvare of |
316 | 53664e15 | Iustin Pop | Just v' -> [( $fnexp, $showJSONE v')] |
317 | 12c19659 | Iustin Pop | Nothing -> [] |
318 | 12c19659 | Iustin Pop | |] |
319 | 53664e15 | Iustin Pop | else [| [( $fnexp, $showJSONE $fvare )] |]) |
320 | 12c19659 | Iustin Pop | |
321 | 12c19659 | Iustin Pop | -- | Generates the \"save\" clause for an entire opcode constructor. |
322 | 12c19659 | Iustin Pop | -- |
323 | 12c19659 | Iustin Pop | -- This matches the opcode with variables named the same as the |
324 | 12c19659 | Iustin Pop | -- constructor fields (just so that the spliced in code looks nicer), |
325 | 12c19659 | Iustin Pop | -- and passes those name plus the parameter definition to 'saveField'. |
326 | 12c19659 | Iustin Pop | saveConstructor :: String -- ^ The constructor name |
327 | 12c19659 | Iustin Pop | -> [OpParam] -- ^ The parameter definitions for this |
328 | 12c19659 | Iustin Pop | -- constructor |
329 | 12c19659 | Iustin Pop | -> Q Clause -- ^ Resulting clause |
330 | 12c19659 | Iustin Pop | saveConstructor sname fields = do |
331 | 12c19659 | Iustin Pop | let cname = mkName sname |
332 | 12c19659 | Iustin Pop | let fnames = map (\(n, _, _) -> mkName n) fields |
333 | 12c19659 | Iustin Pop | let pat = conP cname (map varP fnames) |
334 | 12c19659 | Iustin Pop | let felems = map (uncurry saveField) (zip fnames fields) |
335 | 12c19659 | Iustin Pop | -- now build the OP_ID serialisation |
336 | 53664e15 | Iustin Pop | opid = [| [( $(stringE "OP_ID"), |
337 | 53664e15 | Iustin Pop | $showJSONE $(stringE . deCamelCase $ sname) )] |] |
338 | 12c19659 | Iustin Pop | flist = listE (opid:felems) |
339 | 12c19659 | Iustin Pop | -- and finally convert all this to a json object |
340 | 53664e15 | Iustin Pop | flist' = [| $(varNameE "makeObj") (concat $flist) |] |
341 | 12c19659 | Iustin Pop | clause [pat] (normalB flist') [] |
342 | 12c19659 | Iustin Pop | |
343 | 12c19659 | Iustin Pop | -- | Generates the main save opcode function. |
344 | 12c19659 | Iustin Pop | -- |
345 | 12c19659 | Iustin Pop | -- This builds a per-constructor match clause that contains the |
346 | 12c19659 | Iustin Pop | -- respective constructor-serialisation code. |
347 | 12c19659 | Iustin Pop | genSaveOpCode :: [(String, [OpParam])] -> Q (Dec, Dec) |
348 | 12c19659 | Iustin Pop | genSaveOpCode opdefs = do |
349 | 12c19659 | Iustin Pop | cclauses <- mapM (uncurry saveConstructor) opdefs |
350 | 12c19659 | Iustin Pop | let fname = mkName "saveOpCode" |
351 | 12c19659 | Iustin Pop | sigt <- [t| $(conT (mkName "OpCode")) -> JSON.JSValue |] |
352 | 12c19659 | Iustin Pop | return $ (SigD fname sigt, FunD fname cclauses) |
353 | 12c19659 | Iustin Pop | |
354 | 12c19659 | Iustin Pop | -- | Generates the \"load\" field for a single parameter. |
355 | 12c19659 | Iustin Pop | -- |
356 | 12c19659 | Iustin Pop | -- There is custom handling, depending on how the parameter is |
357 | 12c19659 | Iustin Pop | -- specified. For a 'Maybe' type parameter, we allow that it is not |
358 | 12c19659 | Iustin Pop | -- present (via 'Utils.maybeFromObj'). Otherwise, if there is a |
359 | 12c19659 | Iustin Pop | -- default value, we allow the parameter to be abset, and finally if |
360 | 12c19659 | Iustin Pop | -- there is no default value, we require its presence. |
361 | 12c19659 | Iustin Pop | loadField :: OpParam -> Q (Name, Stmt) |
362 | 12c19659 | Iustin Pop | loadField (fname, qt, qdefa) = do |
363 | 12c19659 | Iustin Pop | let fvar = mkName fname |
364 | 12c19659 | Iustin Pop | t <- qt |
365 | 12c19659 | Iustin Pop | defa <- qdefa |
366 | 12c19659 | Iustin Pop | -- these are used in all patterns below |
367 | 53664e15 | Iustin Pop | let objvar = varNameE "o" |
368 | 53664e15 | Iustin Pop | objfield = stringE fname |
369 | 12c19659 | Iustin Pop | bexp <- if isOptional t |
370 | 53664e15 | Iustin Pop | then [| $((varNameE "maybeFromObj")) $objvar $objfield |] |
371 | 12c19659 | Iustin Pop | else case defa of |
372 | 12c19659 | Iustin Pop | AppE (ConE dt) defval | dt == 'Just -> |
373 | 12c19659 | Iustin Pop | -- but has a default value |
374 | 53664e15 | Iustin Pop | [| $(varNameE "fromObjWithDefault") |
375 | 12c19659 | Iustin Pop | $objvar $objfield $(return defval) |] |
376 | 12c19659 | Iustin Pop | ConE dt | dt == 'Nothing -> |
377 | 53664e15 | Iustin Pop | [| $(varNameE "fromObj") $objvar $objfield |] |
378 | 12c19659 | Iustin Pop | s -> fail $ "Invalid default value " ++ show s ++ |
379 | 12c19659 | Iustin Pop | ", expecting either 'Nothing' or a 'Just defval'" |
380 | 12c19659 | Iustin Pop | return (fvar, BindS (VarP fvar) bexp) |
381 | 12c19659 | Iustin Pop | |
382 | 12c19659 | Iustin Pop | loadConstructor :: String -> [OpParam] -> Q Exp |
383 | 12c19659 | Iustin Pop | loadConstructor sname fields = do |
384 | 12c19659 | Iustin Pop | let name = mkName sname |
385 | 12c19659 | Iustin Pop | fbinds <- mapM loadField fields |
386 | 12c19659 | Iustin Pop | let (fnames, fstmts) = unzip fbinds |
387 | 12c19659 | Iustin Pop | let cval = foldl (\accu fn -> AppE accu (VarE fn)) (ConE name) fnames |
388 | 12c19659 | Iustin Pop | fstmts' = fstmts ++ [NoBindS (AppE (VarE 'return) cval)] |
389 | 12c19659 | Iustin Pop | return $ DoE fstmts' |
390 | 12c19659 | Iustin Pop | |
391 | 12c19659 | Iustin Pop | genLoadOpCode :: [(String, [OpParam])] -> Q (Dec, Dec) |
392 | 12c19659 | Iustin Pop | genLoadOpCode opdefs = do |
393 | 12c19659 | Iustin Pop | let fname = mkName "loadOpCode" |
394 | 12c19659 | Iustin Pop | arg1 = mkName "v" |
395 | 12c19659 | Iustin Pop | objname = mkName "o" |
396 | 12c19659 | Iustin Pop | opid = mkName "op_id" |
397 | 12c19659 | Iustin Pop | st1 <- bindS (varP objname) [| liftM JSON.fromJSObject |
398 | 12c19659 | Iustin Pop | (JSON.readJSON $(varE arg1)) |] |
399 | 53664e15 | Iustin Pop | st2 <- bindS (varP opid) [| $(varNameE "fromObj") |
400 | 53664e15 | Iustin Pop | $(varE objname) $(stringE "OP_ID") |] |
401 | 12c19659 | Iustin Pop | -- the match results (per-constructor blocks) |
402 | 12c19659 | Iustin Pop | mexps <- mapM (uncurry loadConstructor) opdefs |
403 | 12c19659 | Iustin Pop | fails <- [| fail $ "Unknown opcode " ++ $(varE opid) |] |
404 | 12c19659 | Iustin Pop | let mpats = map (\(me, c) -> |
405 | 12c19659 | Iustin Pop | let mp = LitP . StringL . deCamelCase . fst $ c |
406 | 12c19659 | Iustin Pop | in Match mp (NormalB me) [] |
407 | 12c19659 | Iustin Pop | ) $ zip mexps opdefs |
408 | 12c19659 | Iustin Pop | defmatch = Match WildP (NormalB fails) [] |
409 | 12c19659 | Iustin Pop | cst = NoBindS $ CaseE (VarE opid) $ mpats++[defmatch] |
410 | 12c19659 | Iustin Pop | body = DoE [st1, st2, cst] |
411 | 12c19659 | Iustin Pop | sigt <- [t| JSON.JSValue -> JSON.Result $(conT (mkName "OpCode")) |] |
412 | 12c19659 | Iustin Pop | return $ (SigD fname sigt, FunD fname [Clause [VarP arg1] (NormalB body) []]) |
413 | 12c19659 | Iustin Pop | |
414 | 12c19659 | Iustin Pop | -- | No default type. |
415 | 12c19659 | Iustin Pop | noDefault :: Q Exp |
416 | 12c19659 | Iustin Pop | noDefault = conE 'Nothing |
417 | a0090487 | Agata Murawska | |
418 | a0090487 | Agata Murawska | -- * Template code for luxi |
419 | a0090487 | Agata Murawska | |
420 | a0090487 | Agata Murawska | -- | Constructor-to-string for LuxiOp. |
421 | a0090487 | Agata Murawska | genStrOfOp :: Name -> String -> Q [Dec] |
422 | a0090487 | Agata Murawska | genStrOfOp = genConstrToStr id |
423 | a0090487 | Agata Murawska | |
424 | a0090487 | Agata Murawska | -- | Constructor-to-string for MsgKeys. |
425 | a0090487 | Agata Murawska | genStrOfKey :: Name -> String -> Q [Dec] |
426 | a0090487 | Agata Murawska | genStrOfKey = genConstrToStr ensureLower |
427 | a0090487 | Agata Murawska | |
428 | a0090487 | Agata Murawska | -- | LuxiOp parameter type. |
429 | a0090487 | Agata Murawska | type LuxiParam = (String, Q Type, Q Exp) |
430 | a0090487 | Agata Murawska | |
431 | a0090487 | Agata Murawska | -- | Generates the LuxiOp data type. |
432 | a0090487 | Agata Murawska | -- |
433 | a0090487 | Agata Murawska | -- This takes a Luxi operation definition and builds both the |
434 | a0090487 | Agata Murawska | -- datatype and the function trnasforming the arguments to JSON. |
435 | a0090487 | Agata Murawska | -- We can't use anything less generic, because the way different |
436 | a0090487 | Agata Murawska | -- operations are serialized differs on both parameter- and top-level. |
437 | a0090487 | Agata Murawska | -- |
438 | a0090487 | Agata Murawska | -- There are three things to be defined for each parameter: |
439 | a0090487 | Agata Murawska | -- |
440 | a0090487 | Agata Murawska | -- * name |
441 | a0090487 | Agata Murawska | -- |
442 | a0090487 | Agata Murawska | -- * type |
443 | a0090487 | Agata Murawska | -- |
444 | a0090487 | Agata Murawska | -- * operation; this is the operation performed on the parameter before |
445 | a0090487 | Agata Murawska | -- serialization |
446 | a0090487 | Agata Murawska | -- |
447 | b20cbf06 | Iustin Pop | genLuxiOp :: String -> [(String, [LuxiParam])] -> Q [Dec] |
448 | a0090487 | Agata Murawska | genLuxiOp name cons = do |
449 | b20cbf06 | Iustin Pop | decl_d <- mapM (\(cname, fields) -> do |
450 | a0090487 | Agata Murawska | fields' <- mapM (\(_, qt, _) -> |
451 | a0090487 | Agata Murawska | qt >>= \t -> return (NotStrict, t)) |
452 | a0090487 | Agata Murawska | fields |
453 | a0090487 | Agata Murawska | return $ NormalC (mkName cname) fields') |
454 | a0090487 | Agata Murawska | cons |
455 | a0090487 | Agata Murawska | let declD = DataD [] (mkName name) [] decl_d [''Show, ''Read] |
456 | a0090487 | Agata Murawska | (savesig, savefn) <- genSaveLuxiOp cons |
457 | a0090487 | Agata Murawska | return [declD, savesig, savefn] |
458 | a0090487 | Agata Murawska | |
459 | 92678b3c | Iustin Pop | -- | Generates the \"save\" expression for a single luxi parameter. |
460 | b20cbf06 | Iustin Pop | saveLuxiField :: Name -> LuxiParam -> Q Exp |
461 | b20cbf06 | Iustin Pop | saveLuxiField fvar (_, qt, fn) = |
462 | b20cbf06 | Iustin Pop | [| JSON.showJSON ( $(liftM2 appFn fn $ varE fvar) ) |] |
463 | 92678b3c | Iustin Pop | |
464 | a0090487 | Agata Murawska | -- | Generates the \"save\" clause for entire LuxiOp constructor. |
465 | b20cbf06 | Iustin Pop | saveLuxiConstructor :: (String, [LuxiParam]) -> Q Clause |
466 | b20cbf06 | Iustin Pop | saveLuxiConstructor (sname, fields) = do |
467 | a0090487 | Agata Murawska | let cname = mkName sname |
468 | a0090487 | Agata Murawska | fnames = map (\(nm, _, _) -> mkName nm) fields |
469 | a0090487 | Agata Murawska | pat = conP cname (map varP fnames) |
470 | b20cbf06 | Iustin Pop | flist = map (uncurry saveLuxiField) (zip fnames fields) |
471 | b20cbf06 | Iustin Pop | finval = if null flist |
472 | b20cbf06 | Iustin Pop | then [| JSON.showJSON () |] |
473 | b20cbf06 | Iustin Pop | else [| JSON.showJSON $(listE flist) |] |
474 | 92678b3c | Iustin Pop | clause [pat] (normalB finval) [] |
475 | a0090487 | Agata Murawska | |
476 | a0090487 | Agata Murawska | -- | Generates the main save LuxiOp function. |
477 | b20cbf06 | Iustin Pop | genSaveLuxiOp :: [(String, [LuxiParam])]-> Q (Dec, Dec) |
478 | a0090487 | Agata Murawska | genSaveLuxiOp opdefs = do |
479 | a0090487 | Agata Murawska | sigt <- [t| $(conT (mkName "LuxiOp")) -> JSON.JSValue |] |
480 | a0090487 | Agata Murawska | let fname = mkName "opToArgs" |
481 | a0090487 | Agata Murawska | cclauses <- mapM saveLuxiConstructor opdefs |
482 | a0090487 | Agata Murawska | return $ (SigD fname sigt, FunD fname cclauses) |