1 # This file is part of NIT ( http://www.nitlanguage.org ).
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
15 # Instantiation and transformation of semantic nodes in the AST of expressions and statements
18 intrude import semantize
::typing
19 intrude import semantize
::literal
20 intrude import semantize
::parser
21 intrude import semantize
::scope
23 # General factory to build semantic nodes in the AST of expressions
25 # The module used as reference for the building
26 # It is used to gather types and other stufs
29 # The anchor used for some mechanism relying on types
30 var anchor
: nullable MClassType
32 # Make a new Int literal
33 fun make_int
(value
: Int): AIntExpr
35 return new ADecIntExpr.make
(value
, mmodule
.get_primitive_class
("Int").mclass_type
)
38 # Make a new instatiation
39 fun make_new
(callsite
: CallSite, args
: nullable Array[AExpr]): ANewExpr
41 return new ANewExpr.make
(callsite
, args
)
44 # Make a new message send
45 fun make_call
(recv
: AExpr, callsite
: CallSite, args
: nullable Array[AExpr]): ACallExpr
47 return new ACallExpr.make
(recv
, callsite
, args
)
50 # Make a new, empty, sequence of statements
51 fun make_block
: ABlockExpr
53 return new ABlockExpr.make
56 # Make a new, empty, loop of statements
57 fun make_loop
: ALoopExpr
59 return new ALoopExpr.make
62 # Make a new variable read
63 fun make_var_read
(variable
: Variable, mtype
: MType): AVarExpr
65 return new AVarExpr.make
(variable
, mtype
)
68 # Make a new variable assignment
69 fun make_var_assign
(variable
: Variable, value
: AExpr): AVarAssignExpr
71 return new AVarAssignExpr.make
(variable
, value
)
74 # Make a new attribute read
75 fun make_attr_read
(recv
: AExpr, attribute
: MAttribute): AAttrExpr
77 var mtype
= attribute
.intro
.static_mtype
.resolve_for
(recv
.mtype
.as(not null), anchor
, mmodule
, true)
78 return new AAttrExpr.make
(recv
, attribute
, mtype
)
81 # Make a new attribute assignment
82 fun make_attr_assign
(recv
: AExpr, attribute
: MAttribute, value
: AExpr): AAttrAssignExpr
84 return new AAttrAssignExpr.make
(recv
, attribute
, value
)
87 # Make a new escapable block
90 return new ADoExpr.make
93 # Make a new break for a given escapemark
94 fun make_break
(escapemark
: EscapeMark): ABreakExpr
96 return new ABreakExpr.make
(escapemark
)
99 # Make a new condinionnal
100 # `mtype` is the return type of the whole if, in case of a ternary operator.
101 fun make_if
(condition
: AExpr, mtype
: nullable MType): AIfExpr
103 return new AIfExpr.make
(condition
, mtype
)
108 # Return a new variable read that contains the value of the expression
109 # This method take care efficiently of creating and initalising an anonymous local variable
111 # Note: since this method do side-effects (AST replacement), there could be unexpected effects when used as
112 # argument of other methods related to AST transformations.
113 fun make_var_read
: AVarExpr
115 var variable
= self.variable_cache
116 if variable
== null then
117 assert parent
!= null
118 var place
= detach_with_placeholder
119 variable
= new Variable("")
120 variable
.declared_type
= self.mtype
121 var nvar
= new AVarAssignExpr.make
(variable
, self)
122 place
.replace_with
(nvar
)
123 self.variable_cache
= variable
125 return new AVarExpr.make
(variable
, variable
.declared_type
.as(not null))
128 private var variable_cache
: nullable Variable
130 # The `detach` method completely remove the node in the parent.
131 # Owever, sometime, it is useful to keep the emplacement of the removed child.
133 # The standard usecase is the insertion of a node beetwen a parent `p` and a child `p.c`.
134 # To create the new node `n`, we need to attach the child to it.
135 # But, to put `n` where `c` was in `p`, the place has to be remembered.
139 # var h = c.detach_with_placeholder
140 # var n = astbuilder.make_XXX(c)
142 fun detach_with_placeholder
: AExpr
144 var h
= new APlaceholderExpr.make
150 # Add `expr` at the end of the block
152 # REQUIRE: self isa ABlockExpr
154 # Note: this method, aimed to `ABlockExpr` is promoted to `AExpr` because of the limitations of the hierarchies generated by sablecc3
157 print
"add not implemented in {inspect}"
162 # A placeholder for a `AExpr` node
163 # Instances are transiantly used to mark some specific emplacments in the AST
164 # during complex transformations.
166 # Their must not appear in a valid AST
168 # @see AExpr::detach_with_placeholder
169 class APlaceholderExpr
176 redef class ABlockExpr
182 redef fun add
(expr
: AExpr)
188 redef class ALoopExpr
191 _n_kwloop
= new TKwloop
193 n_block
= new ABlockExpr
194 n_block
.is_typed
= true
197 redef fun add
(expr
: AExpr)
208 n_block
= new ABlockExpr
209 n_block
.is_typed
= true
212 # Make a new break expression of the given do
213 fun make_break
: ABreakExpr
215 var escapemark
= self.break_mark
216 if escapemark
== null then
217 escapemark
= new EscapeMark(null)
218 self.break_mark
= escapemark
220 return new ABreakExpr.make
(escapemark
)
223 redef fun add
(expr
: AExpr)
229 redef class ABreakExpr
230 private init make
(escapemark
: EscapeMark)
232 _n_kwbreak
= new TKwbreak
233 self.escapemark
= escapemark
234 escapemark
.escapes
.add
self
240 private init make
(condition
: AExpr, mtype
: nullable MType)
244 _n_expr
.parent
= self
245 _n_then
= new ABlockExpr.make
246 _n_else
= new ABlockExpr.make
259 redef class ADecIntExpr
260 private init make
(value
: Int, t
: MType)
263 self._n_number
= new TNumber # dummy
269 private init make
(callsite
: CallSite, args
: nullable Array[AExpr])
271 _n_kwnew
= new TKwnew
272 _n_type
= new AType.make
273 _n_args
= new AListExprs
275 n_args
.n_exprs
.add_all
(args
)
277 self.callsite
= callsite
278 self.recvtype
= callsite
.recv
.as(MClassType)
279 if callsite
.mproperty
.is_new
then
280 self.mtype
= callsite
.msignature
.return_mtype
282 self.mtype
= callsite
.recv
288 redef class ACallExpr
289 private init make
(recv
: AExpr, callsite
: CallSite, args
: nullable Array[AExpr])
292 _n_args
= new AListExprs
295 self.n_args
.n_exprs
.add_all
(args
)
297 self.callsite
= callsite
298 self.mtype
= callsite
.msignature
.return_mtype
303 redef class AAttrExpr
304 private init make
(recv
: AExpr, attribute
: MAttribute, t
: MType)
309 mproperty
= attribute
314 redef class AAttrAssignExpr
315 private init make
(recv
: AExpr, attribute
: MAttribute, value
: AExpr)
322 _n_assign
= new TAssign
323 mproperty
= attribute
329 private init make
(v
: Variable, mtype
: MType)
337 redef class AVarAssignExpr
338 private init make
(v
: Variable, value
: AExpr)
343 _n_assign
= new TAssign