Creating AST for shared and local variables
- by Rizwan Abbasi
Here is my grammar
grammar simulator;
options {
language = Java;
output = AST;
ASTLabelType=CommonTree;
}
//imaginary tokens
tokens{
SHARED;
LOCALS;
BOOL;
RANGE;
ARRAY;
}
parse
: declaration+
;
declaration
:variables
;
variables
: locals
;
locals
: (bool
| range
| array)
;
bool
:ID 'in' '[' ID ',' ID ']' ('init' ID)? -> ^(BOOL ID ID ID ID?)
;
range
: ID 'in' '[' INT '..' INT ']' ('init' INT)? -> ^(RANGE ID INT INT INT?)
;
array
:ID 'in' 'array' 'of' '[' INT '..' INT ']' ('init' INT)? -> ^(ARRAY ID INT INT INT?)
;
ID
: (('a'..'z' | 'A'..'Z'|'_')('a'..'z' | 'A'..'Z'|'0'..'9'|'_'))*
;
INT
: ('0'..'9')+
;
WHITESPACE
: ('\t' | ' ' | '\r' | '\n' | '\u000C')+ {$channel = HIDDEN;}
;
INPUT
flag in [down, up] init down
pc in [0..7] init 0
CA in array of [0..5] init 0
AST
It is having a small problem. Variables (bool, range or array) can be of two abstract types
1. locals (each object will have it's own variable)
2. shared (think of static in java, same for all object)
Now the requirements are changed. I want the user to input like this
NEW INPUT
domains:
upDown [up,down]
possibleStates [0-7]
booleans [true,false]
locals:
pc in possibleStates init 0
flag in upDown init down
flag1 in upDown init down
map in array of booleans init false
shared:
pcs in possibleStates init 0
flag in upDown init down
flag1 in upDown init down
maps in array of booleans init false
Again, all the variables can be of two types (of any domain sepecified)
1. Local
2. Shared
In Domains:
upDown [up,down]
possibleStates [0-7]
upDown, up, down and possibleStates are of type ID (ID is defined in my above grammar), 0 and 7 are of type INT
Can any body help me how to convert my current grammar to meet new specifications.
