https://github.com/mloncode/uast2pl
Universal Abstract Syntax Tree to Prolog
https://github.com/mloncode/uast2pl
bblfsh prolog syntax-tree transpiler uast
Last synced: 5 months ago
JSON representation
Universal Abstract Syntax Tree to Prolog
- Host: GitHub
- URL: https://github.com/mloncode/uast2pl
- Owner: mloncode
- License: gpl-3.0
- Created: 2019-10-07T09:31:23.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2022-05-14T10:04:40.000Z (about 4 years ago)
- Last Synced: 2025-10-01T05:24:58.355Z (8 months ago)
- Topics: bblfsh, prolog, syntax-tree, transpiler, uast
- Language: Go
- Homepage:
- Size: 481 KB
- Stars: 12
- Watchers: 6
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# uast2pl
is kind of [Universal Abstract Syntax Tree](https://doc.bblf.sh/uast/uast-specification-v2.html) to Prolog transpiler.
It takes *UAST* node as an input and tries to produce equivalent prolog program.
### Tools
- `./uast2pl -f input-source.file [-f input-source.file2 -f ...] [-o output-prolog.file] [-s babelfish-server]`.
Transforms source code into _uast_ (thanks to babelfish) and next transforms _uast_ into a prolog representation.
```
go build ./cmd/uast2pl
./uast2pl --help
Usage of ./uast2pl:
-f value
list of input source files
-o string
output file (by default stdio)
-s string
address:port of babelfish server (default "localhost:9432")
```
- `./qpl -f input-prolog.file [-f input-prolog.file2 -f ...] [-o output.file] -q "query(Var)."`.
Embedded [_wam_](https://en.wikipedia.org/wiki/Warren_Abstract_Machine) lets query prolog DB.
```
go build ./cmd/qpl/
./qpl --help
Usage of ./qpl:
-f value
list of input prolog files
-q string
prolog query
-o string
output file (by default stdio)
```
### Example (extract function name and arguments)
For a given `examples/python/fib.py` file:
```python
def fib(n, a = 0, b = 1):
if n == 0:
return a
if n == 1:
return b
return fib(n - 1, b, a + b);
```
we get following UAST
```
{ '@type': "python:Module",
'@role': [File, Module],
'@pos': { '@type': "uast:Positions",
},
body: [
{ '@type': "uast:FunctionGroup",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 4,
line: 1,
col: 5,
},
end: { '@type': "uast:Position",
offset: 7,
line: 1,
col: 8,
},
},
Nodes: [
{
async: false,
comments: {},
decorators: [],
},
{ '@type': "uast:Alias",
Name: { '@type': "uast:Identifier",
Name: "fib",
},
Node: { '@type': "uast:Function",
Body: { '@type': "uast:Block",
Statements: [
{ '@type': "python:If",
'@token': "if",
'@role': [Expression, If],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 30,
line: 2,
col: 5,
},
end: { '@type': "uast:Position",
offset: 32,
line: 2,
col: 7,
},
},
body: { '@type': "python:If.body",
'@role': [Body, If, Then],
'body_stmts': [
{ '@type': "python:Return",
'@token': "return",
'@role': [Return, Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 49,
line: 3,
col: 9,
},
end: { '@type': "uast:Position",
offset: 55,
line: 3,
col: 15,
},
},
value: { '@type': "python:BoxedName",
'@role': [Unannotated],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 56,
line: 3,
col: 16,
},
end: { '@type': "uast:Position",
offset: 57,
line: 3,
col: 17,
},
},
Name: "a",
},
ctx: "Load",
},
},
],
},
orelse: { '@type': "python:If.orelse",
'@token': "else",
'@role': [Body, Else, If],
'else_stmts': [],
},
test: { '@type': "python:Compare",
'@role': [Binary, Condition, Expression, If],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 33,
line: 2,
col: 8,
},
},
comparators: { '@type': "python:Compare.comparators",
'@role': [Expression, Right],
comparators: [
{ '@type': "python:Num",
'@token': 0,
'@role': [Expression, Literal, Number, Primitive],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 38,
line: 2,
col: 13,
},
end: { '@type': "uast:Position",
offset: 39,
line: 2,
col: 14,
},
},
},
],
},
left: { '@type': "python:BoxedName",
'@role': [Expression, Left],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 33,
line: 2,
col: 8,
},
end: { '@type': "uast:Position",
offset: 34,
line: 2,
col: 9,
},
},
Name: "n",
},
ctx: "Load",
},
ops: { '@type': "python:Compare.ops",
'@role': [Expression],
ops: [
{ '@type': "python:Eq",
'@token': "==",
'@role': [Equal, Operator, Relational],
'@pos': { '@type': "uast:Positions",
},
},
],
},
},
},
{ '@type': "python:If",
'@token': "if",
'@role': [Expression, If],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 62,
line: 4,
col: 5,
},
end: { '@type': "uast:Position",
offset: 64,
line: 4,
col: 7,
},
},
body: { '@type': "python:If.body",
'@role': [Body, If, Then],
'body_stmts': [
{ '@type': "python:Return",
'@token': "return",
'@role': [Return, Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 81,
line: 5,
col: 9,
},
end: { '@type': "uast:Position",
offset: 87,
line: 5,
col: 15,
},
},
value: { '@type': "python:BoxedName",
'@role': [Unannotated],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 88,
line: 5,
col: 16,
},
end: { '@type': "uast:Position",
offset: 89,
line: 5,
col: 17,
},
},
Name: "b",
},
ctx: "Load",
},
},
],
},
orelse: { '@type': "python:If.orelse",
'@token': "else",
'@role': [Body, Else, If],
'else_stmts': [],
},
test: { '@type': "python:Compare",
'@role': [Binary, Condition, Expression, If],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 65,
line: 4,
col: 8,
},
},
comparators: { '@type': "python:Compare.comparators",
'@role': [Expression, Right],
comparators: [
{ '@type': "python:Num",
'@token': 1,
'@role': [Expression, Literal, Number, Primitive],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 70,
line: 4,
col: 13,
},
end: { '@type': "uast:Position",
offset: 71,
line: 4,
col: 14,
},
},
},
],
},
left: { '@type': "python:BoxedName",
'@role': [Expression, Left],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 65,
line: 4,
col: 8,
},
end: { '@type': "uast:Position",
offset: 66,
line: 4,
col: 9,
},
},
Name: "n",
},
ctx: "Load",
},
ops: { '@type': "python:Compare.ops",
'@role': [Expression],
ops: [
{ '@type': "python:Eq",
'@token': "==",
'@role': [Equal, Operator, Relational],
'@pos': { '@type': "uast:Positions",
},
},
],
},
},
},
{ '@type': "python:Return",
'@token': "return",
'@role': [Return, Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 94,
line: 6,
col: 5,
},
end: { '@type': "uast:Position",
offset: 100,
line: 6,
col: 11,
},
},
value: { '@type': "python:Call",
'@role': [Call, Expression, Function],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 101,
line: 6,
col: 12,
},
},
args: [
{ '@type': "python:BinOp",
'@role': [Argument, Binary, Call, Expression, Function, Name, Positional],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 105,
line: 6,
col: 16,
},
},
left: { '@type': "python:BoxedName",
'@role': [Binary, Expression, Left],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 105,
line: 6,
col: 16,
},
end: { '@type': "uast:Position",
offset: 106,
line: 6,
col: 17,
},
},
Name: "n",
},
ctx: "Load",
},
op: { '@type': "python:Sub",
'@token': "-",
'@role': [Arithmetic, Binary, Operator, Substract],
'@pos': { '@type': "uast:Positions",
},
},
right: { '@type': "python:Num",
'@token': 1,
'@role': [Binary, Expression, Literal, Number, Primitive, Right],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 109,
line: 6,
col: 20,
},
end: { '@type': "uast:Position",
offset: 110,
line: 6,
col: 21,
},
},
},
},
{ '@type': "python:BoxedName",
'@role': [Argument, Call, Function, Name, Positional],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 112,
line: 6,
col: 23,
},
end: { '@type': "uast:Position",
offset: 113,
line: 6,
col: 24,
},
},
Name: "b",
},
ctx: "Load",
},
{ '@type': "python:BinOp",
'@role': [Argument, Binary, Call, Expression, Function, Name, Positional],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 115,
line: 6,
col: 26,
},
},
left: { '@type': "python:BoxedName",
'@role': [Binary, Expression, Left],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 115,
line: 6,
col: 26,
},
end: { '@type': "uast:Position",
offset: 116,
line: 6,
col: 27,
},
},
Name: "a",
},
ctx: "Load",
},
op: { '@type': "python:Add",
'@token': "+",
'@role': [Add, Arithmetic, Binary, Operator],
'@pos': { '@type': "uast:Positions",
},
},
right: { '@type': "python:BoxedName",
'@role': [Binary, Expression, Right],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 119,
line: 6,
col: 30,
},
end: { '@type': "uast:Position",
offset: 120,
line: 6,
col: 31,
},
},
Name: "b",
},
ctx: "Load",
},
},
],
func: { '@type': "python:BoxedName",
'@role': [Call, Callee],
'boxed_value': { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 101,
line: 6,
col: 12,
},
end: { '@type': "uast:Position",
offset: 104,
line: 6,
col: 15,
},
},
Name: "fib",
},
ctx: "Load",
},
keywords: [],
},
},
],
},
Type: { '@type': "uast:FunctionType",
Arguments: [
{ '@type': "uast:Argument",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 8,
line: 1,
col: 9,
},
end: { '@type': "uast:Position",
offset: 9,
line: 1,
col: 10,
},
},
MapVariadic: false,
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 8,
line: 1,
col: 9,
},
end: { '@type': "uast:Position",
offset: 9,
line: 1,
col: 10,
},
},
Name: "n",
},
Receiver: false,
Type: ~,
Variadic: false,
},
{ '@type': "uast:Argument",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 11,
line: 1,
col: 12,
},
end: { '@type': "uast:Position",
offset: 12,
line: 1,
col: 13,
},
},
Init: { '@type': "python:Num",
'@token': 0,
'@role': [Expression, Literal, Number, Primitive],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 15,
line: 1,
col: 16,
},
end: { '@type': "uast:Position",
offset: 16,
line: 1,
col: 17,
},
},
},
MapVariadic: false,
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 11,
line: 1,
col: 12,
},
end: { '@type': "uast:Position",
offset: 12,
line: 1,
col: 13,
},
},
Name: "a",
},
Receiver: false,
Type: ~,
Variadic: false,
},
{ '@type': "uast:Argument",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 18,
line: 1,
col: 19,
},
end: { '@type': "uast:Position",
offset: 19,
line: 1,
col: 20,
},
},
Init: { '@type': "python:Num",
'@token': 1,
'@role': [Expression, Literal, Number, Primitive],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 22,
line: 1,
col: 23,
},
end: { '@type': "uast:Position",
offset: 23,
line: 1,
col: 24,
},
},
},
MapVariadic: false,
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 18,
line: 1,
col: 19,
},
end: { '@type': "uast:Position",
offset: 19,
line: 1,
col: 20,
},
},
Name: "b",
},
Receiver: false,
Type: ~,
Variadic: false,
},
],
Returns: [
{ '@type': "uast:Argument",
Init: { '@type': "uast:Identifier",
Name: "None",
},
MapVariadic: false,
Name: ~,
Receiver: false,
Type: ~,
Variadic: false,
},
],
},
},
},
],
},
],
}
```
what can be transformed into a prolog program
```prolog
positions0(['uast:Positions', _, _]).
value0('File').
value1('Module').
array0([Arg0,Arg1]) :- value0(Arg0),value1(Arg1).
value2('python:Module').
position0(['uast:Position', 5, 1, 4]).
position1(['uast:Position', 8, 1, 7]).
positions1(['uast:Positions', Start, End]) :- position0(Start), position1(End).
array1([]).
value3(false).
object0(_).
object1(Obj) :- value3(Obj), !.
object1(Obj) :- object0(Obj), !.
object1(Obj) :- array1(Obj), !.
positions2(['uast:Positions', _, _]).
positions3(['uast:Positions', _, _]).
position2(['uast:Position', 9, 1, 8]).
position3(['uast:Position', 10, 1, 9]).
positions4(['uast:Positions', Start, End]) :- position2(Start), position3(End).
role0('Identifier').
identifier0(['uast:Identifier', 'n', Pos, [Role0]]) :- positions4(Pos),role0(Role0).
positions5(['uast:Positions', Start, End]) :- position2(Start), position3(End).
argument0(['uast:Argument', Name, _, _, false, false, false, Pos]) :- identifier0(Name),positions5(Pos).
position4(['uast:Position', 12, 1, 11]).
position5(['uast:Position', 13, 1, 12]).
positions6(['uast:Positions', Start, End]) :- position4(Start), position5(End).
identifier1(['uast:Identifier', 'a', Pos, [Role0]]) :- positions6(Pos),role0(Role0).
position6(['uast:Position', 16, 1, 15]).
position7(['uast:Position', 17, 1, 16]).
positions7(['uast:Positions', Start, End]) :- position6(Start), position7(End).
value4('Expression').
value5('Literal').
value6('Number').
value7('Primitive').
array2([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value5(Arg1),value6(Arg2),value7(Arg3).
value8('python:Num').
value9(0).
object2(Obj) :- positions7(Obj), !.
object2(Obj) :- array2(Obj), !.
object2(Obj) :- value8(Obj), !.
object2(Obj) :- value9(Obj), !.
positions8(['uast:Positions', Start, End]) :- position4(Start), position5(End).
argument1(['uast:Argument', Name, _, Init, false, false, false, Pos]) :- identifier1(Name),object2(Init),positions8(Pos).
position8(['uast:Position', 19, 1, 18]).
position9(['uast:Position', 20, 1, 19]).
positions9(['uast:Positions', Start, End]) :- position8(Start), position9(End).
identifier2(['uast:Identifier', 'b', Pos, [Role0]]) :- positions9(Pos),role0(Role0).
value10(1).
position10(['uast:Position', 23, 1, 22]).
position11(['uast:Position', 24, 1, 23]).
positions10(['uast:Positions', Start, End]) :- position10(Start), position11(End).
array3([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value5(Arg1),value6(Arg2),value7(Arg3).
object3(Obj) :- value8(Obj), !.
object3(Obj) :- value10(Obj), !.
object3(Obj) :- positions10(Obj), !.
object3(Obj) :- array3(Obj), !.
positions11(['uast:Positions', Start, End]) :- position8(Start), position9(End).
argument2(['uast:Argument', Name, _, Init, false, false, false, Pos]) :- identifier2(Name),object3(Init),positions11(Pos).
positions12(['uast:Positions', _, _]).
identifier3(['uast:Identifier', 'None', Pos, [Role0]]) :- positions12(Pos),role0(Role0).
positions13(['uast:Positions', _, _]).
argument3(['uast:Argument', _, _, Init, false, false, false, Pos]) :- identifier3(Init),positions13(Pos).
function_type0(['uast:FunctionType', [Arg0,Arg1,Arg2], [Ret0], Pos]) :- argument0(Arg0),argument1(Arg1),argument2(Arg2),argument3(Ret0),positions3(Pos).
positions14(['uast:Positions', _, _]).
value11('If').
array4([Arg0,Arg1]) :- value11(Arg0),value4(Arg1).
value12('python:If').
value13('python:If.body').
position12(['uast:Position', 9, 3, 49]).
position13(['uast:Position', 15, 3, 55]).
positions15(['uast:Positions', Start, End]) :- position12(Start), position13(End).
value14('Return').
value15('Statement').
array5([Arg0,Arg1]) :- value14(Arg0),value15(Arg1).
value16('python:Return').
value17('return').
position14(['uast:Position', 16, 3, 56]).
position15(['uast:Position', 17, 3, 57]).
positions16(['uast:Positions', Start, End]) :- position14(Start), position15(End).
identifier4(['uast:Identifier', 'a', Pos, [Role0]]) :- positions16(Pos),role0(Role0).
value18('Load').
value19('python:BoxedName').
object4(Obj) :- identifier4(Obj), !.
object4(Obj) :- value18(Obj), !.
object4(Obj) :- value19(Obj), !.
object5(Obj) :- positions15(Obj), !.
object5(Obj) :- array5(Obj), !.
object5(Obj) :- value16(Obj), !.
object5(Obj) :- value17(Obj), !.
object5(Obj) :- object4(Obj), !.
array6([Arg0]) :- object5(Arg0).
value20('Body').
value21('Then').
array7([Arg0,Arg1,Arg2]) :- value11(Arg0),value20(Arg1),value21(Arg2).
object6(Obj) :- array6(Obj), !.
object6(Obj) :- array7(Obj), !.
object6(Obj) :- value13(Obj), !.
value22('if').
value23('Else').
array8([Arg0,Arg1,Arg2]) :- value11(Arg0),value20(Arg1),value23(Arg2).
value24('python:If.orelse').
value25('else').
array9([]).
object7(Obj) :- array9(Obj), !.
object7(Obj) :- array8(Obj), !.
object7(Obj) :- value24(Obj), !.
object7(Obj) :- value25(Obj), !.
position16(['uast:Position', 8, 2, 33]).
positions17(['uast:Positions', Start, _]) :- position16(Start).
value26('Binary').
value27('Condition').
array10([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value26(Arg1),value27(Arg2),value11(Arg3).
value28('python:Compare').
value29('Right').
array11([Arg0,Arg1]) :- value4(Arg0),value29(Arg1).
value30('python:Compare.comparators').
position17(['uast:Position', 13, 2, 38]).
position18(['uast:Position', 14, 2, 39]).
positions18(['uast:Positions', Start, End]) :- position17(Start), position18(End).
array12([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value5(Arg1),value6(Arg2),value7(Arg3).
object8(Obj) :- value9(Obj), !.
object8(Obj) :- positions18(Obj), !.
object8(Obj) :- array12(Obj), !.
object8(Obj) :- value8(Obj), !.
array13([Arg0]) :- object8(Arg0).
object9(Obj) :- array11(Obj), !.
object9(Obj) :- value30(Obj), !.
object9(Obj) :- array13(Obj), !.
value31('Left').
array14([Arg0,Arg1]) :- value4(Arg0),value31(Arg1).
position19(['uast:Position', 9, 2, 34]).
positions19(['uast:Positions', Start, End]) :- position16(Start), position19(End).
identifier5(['uast:Identifier', 'n', Pos, [Role0]]) :- positions19(Pos),role0(Role0).
object10(Obj) :- array14(Obj), !.
object10(Obj) :- value19(Obj), !.
object10(Obj) :- identifier5(Obj), !.
object10(Obj) :- value18(Obj), !.
array15([Arg0]) :- value4(Arg0).
value32('python:Compare.ops').
positions20(['uast:Positions', _, _]).
value33('Operator').
value34('Relational').
value35('Equal').
array16([Arg0,Arg1,Arg2]) :- value33(Arg0),value34(Arg1),value35(Arg2).
value36('python:Eq').
value37('==').
object11(Obj) :- array16(Obj), !.
object11(Obj) :- value36(Obj), !.
object11(Obj) :- value37(Obj), !.
object11(Obj) :- positions20(Obj), !.
array17([Arg0]) :- object11(Arg0).
object12(Obj) :- array15(Obj), !.
object12(Obj) :- value32(Obj), !.
object12(Obj) :- array17(Obj), !.
object13(Obj) :- object10(Obj), !.
object13(Obj) :- object12(Obj), !.
object13(Obj) :- positions17(Obj), !.
object13(Obj) :- array10(Obj), !.
object13(Obj) :- value28(Obj), !.
object13(Obj) :- object9(Obj), !.
position20(['uast:Position', 5, 2, 30]).
position21(['uast:Position', 7, 2, 32]).
positions21(['uast:Positions', Start, End]) :- position20(Start), position21(End).
object14(Obj) :- positions21(Obj), !.
object14(Obj) :- array4(Obj), !.
object14(Obj) :- value12(Obj), !.
object14(Obj) :- object6(Obj), !.
object14(Obj) :- value22(Obj), !.
object14(Obj) :- object7(Obj), !.
object14(Obj) :- object13(Obj), !.
position22(['uast:Position', 5, 4, 62]).
position23(['uast:Position', 7, 4, 64]).
positions22(['uast:Positions', Start, End]) :- position22(Start), position23(End).
array18([Arg0,Arg1]) :- value11(Arg0),value4(Arg1).
array19([Arg0,Arg1,Arg2]) :- value11(Arg0),value20(Arg1),value21(Arg2).
position24(['uast:Position', 9, 5, 81]).
position25(['uast:Position', 15, 5, 87]).
positions23(['uast:Positions', Start, End]) :- position24(Start), position25(End).
array20([Arg0,Arg1]) :- value14(Arg0),value15(Arg1).
position26(['uast:Position', 16, 5, 88]).
position27(['uast:Position', 17, 5, 89]).
positions24(['uast:Positions', Start, End]) :- position26(Start), position27(End).
identifier6(['uast:Identifier', 'b', Pos, [Role0]]) :- positions24(Pos),role0(Role0).
object15(Obj) :- identifier6(Obj), !.
object15(Obj) :- value18(Obj), !.
object15(Obj) :- value19(Obj), !.
object16(Obj) :- positions23(Obj), !.
object16(Obj) :- array20(Obj), !.
object16(Obj) :- value16(Obj), !.
object16(Obj) :- value17(Obj), !.
object16(Obj) :- object15(Obj), !.
array21([Arg0]) :- object16(Arg0).
object17(Obj) :- array19(Obj), !.
object17(Obj) :- value13(Obj), !.
object17(Obj) :- array21(Obj), !.
array22([Arg0,Arg1,Arg2]) :- value11(Arg0),value20(Arg1),value23(Arg2).
array23([]).
object18(Obj) :- array22(Obj), !.
object18(Obj) :- value24(Obj), !.
object18(Obj) :- value25(Obj), !.
object18(Obj) :- array23(Obj), !.
position28(['uast:Position', 13, 4, 70]).
position29(['uast:Position', 14, 4, 71]).
positions25(['uast:Positions', Start, End]) :- position28(Start), position29(End).
array24([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value5(Arg1),value6(Arg2),value7(Arg3).
object19(Obj) :- value10(Obj), !.
object19(Obj) :- positions25(Obj), !.
object19(Obj) :- array24(Obj), !.
object19(Obj) :- value8(Obj), !.
array25([Arg0]) :- object19(Arg0).
array26([Arg0,Arg1]) :- value4(Arg0),value29(Arg1).
object20(Obj) :- array25(Obj), !.
object20(Obj) :- array26(Obj), !.
object20(Obj) :- value30(Obj), !.
position30(['uast:Position', 8, 4, 65]).
position31(['uast:Position', 9, 4, 66]).
positions26(['uast:Positions', Start, End]) :- position30(Start), position31(End).
identifier7(['uast:Identifier', 'n', Pos, [Role0]]) :- positions26(Pos),role0(Role0).
array27([Arg0,Arg1]) :- value4(Arg0),value31(Arg1).
object21(Obj) :- array27(Obj), !.
object21(Obj) :- value19(Obj), !.
object21(Obj) :- identifier7(Obj), !.
object21(Obj) :- value18(Obj), !.
positions27(['uast:Positions', _, _]).
array28([Arg0,Arg1,Arg2]) :- value33(Arg0),value34(Arg1),value35(Arg2).
object22(Obj) :- value36(Obj), !.
object22(Obj) :- value37(Obj), !.
object22(Obj) :- positions27(Obj), !.
object22(Obj) :- array28(Obj), !.
array29([Arg0]) :- object22(Arg0).
array30([Arg0]) :- value4(Arg0).
object23(Obj) :- value32(Obj), !.
object23(Obj) :- array29(Obj), !.
object23(Obj) :- array30(Obj), !.
positions28(['uast:Positions', Start, _]) :- position30(Start).
array31([Arg0,Arg1,Arg2,Arg3]) :- value4(Arg0),value26(Arg1),value27(Arg2),value11(Arg3).
object24(Obj) :- object23(Obj), !.
object24(Obj) :- positions28(Obj), !.
object24(Obj) :- array31(Obj), !.
object24(Obj) :- value28(Obj), !.
object24(Obj) :- object20(Obj), !.
object24(Obj) :- object21(Obj), !.
object25(Obj) :- object24(Obj), !.
object25(Obj) :- positions22(Obj), !.
object25(Obj) :- array18(Obj), !.
object25(Obj) :- value12(Obj), !.
object25(Obj) :- object17(Obj), !.
object25(Obj) :- value22(Obj), !.
object25(Obj) :- object18(Obj), !.
value38('Function').
value39('Call').
array32([Arg0,Arg1,Arg2]) :- value38(Arg0),value39(Arg1),value4(Arg2).
value40('python:Call').
position32(['uast:Position', 16, 6, 105]).
positions29(['uast:Positions', Start, _]) :- position32(Start).
value41('Positional').
value42('Argument').
value43('Name').
array33([Arg0,Arg1,Arg2,Arg3,Arg4,Arg5,Arg6]) :- value4(Arg0),value26(Arg1),value38(Arg2),value39(Arg3),value41(Arg4),value42(Arg5),value43(Arg6).
value44('python:BinOp').
position33(['uast:Position', 17, 6, 106]).
positions30(['uast:Positions', Start, End]) :- position32(Start), position33(End).
identifier8(['uast:Identifier', 'n', Pos, [Role0]]) :- positions30(Pos),role0(Role0).
array34([Arg0,Arg1,Arg2]) :- value4(Arg0),value26(Arg1),value31(Arg2).
object26(Obj) :- value19(Obj), !.
object26(Obj) :- identifier8(Obj), !.
object26(Obj) :- value18(Obj), !.
object26(Obj) :- array34(Obj), !.
value45('-').
positions31(['uast:Positions', _, _]).
value46('Arithmetic').
value47('Substract').
array35([Arg0,Arg1,Arg2,Arg3]) :- value33(Arg0),value46(Arg1),value47(Arg2),value26(Arg3).
value48('python:Sub').
object27(Obj) :- array35(Obj), !.
object27(Obj) :- value48(Obj), !.
object27(Obj) :- value45(Obj), !.
object27(Obj) :- positions31(Obj), !.
position34(['uast:Position', 20, 6, 109]).
position35(['uast:Position', 21, 6, 110]).
positions32(['uast:Positions', Start, End]) :- position34(Start), position35(End).
array36([Arg0,Arg1,Arg2,Arg3,Arg4,Arg5]) :- value4(Arg0),value5(Arg1),value6(Arg2),value7(Arg3),value26(Arg4),value29(Arg5).
object28(Obj) :- positions32(Obj), !.
object28(Obj) :- array36(Obj), !.
object28(Obj) :- value8(Obj), !.
object28(Obj) :- value10(Obj), !.
object29(Obj) :- positions29(Obj), !.
object29(Obj) :- array33(Obj), !.
object29(Obj) :- value44(Obj), !.
object29(Obj) :- object26(Obj), !.
object29(Obj) :- object27(Obj), !.
object29(Obj) :- object28(Obj), !.
array37([Arg0,Arg1,Arg2,Arg3,Arg4]) :- value38(Arg0),value39(Arg1),value41(Arg2),value42(Arg3),value43(Arg4).
position36(['uast:Position', 23, 6, 112]).
position37(['uast:Position', 24, 6, 113]).
positions33(['uast:Positions', Start, End]) :- position36(Start), position37(End).
identifier9(['uast:Identifier', 'b', Pos, [Role0]]) :- positions33(Pos),role0(Role0).
object30(Obj) :- value19(Obj), !.
object30(Obj) :- identifier9(Obj), !.
object30(Obj) :- value18(Obj), !.
object30(Obj) :- array37(Obj), !.
position38(['uast:Position', 26, 6, 115]).
positions34(['uast:Positions', Start, _]) :- position38(Start).
array38([Arg0,Arg1,Arg2,Arg3,Arg4,Arg5,Arg6]) :- value4(Arg0),value26(Arg1),value38(Arg2),value39(Arg3),value41(Arg4),value42(Arg5),value43(Arg6).
position39(['uast:Position', 27, 6, 116]).
positions35(['uast:Positions', Start, End]) :- position38(Start), position39(End).
identifier10(['uast:Identifier', 'a', Pos, [Role0]]) :- positions35(Pos),role0(Role0).
array39([Arg0,Arg1,Arg2]) :- value4(Arg0),value26(Arg1),value31(Arg2).
object31(Obj) :- value19(Obj), !.
object31(Obj) :- identifier10(Obj), !.
object31(Obj) :- value18(Obj), !.
object31(Obj) :- array39(Obj), !.
value49('+').
positions36(['uast:Positions', _, _]).
value50('Add').
array40([Arg0,Arg1,Arg2,Arg3]) :- value33(Arg0),value46(Arg1),value50(Arg2),value26(Arg3).
value51('python:Add').
object32(Obj) :- value51(Obj), !.
object32(Obj) :- value49(Obj), !.
object32(Obj) :- positions36(Obj), !.
object32(Obj) :- array40(Obj), !.
array41([Arg0,Arg1,Arg2]) :- value4(Arg0),value26(Arg1),value29(Arg2).
position40(['uast:Position', 30, 6, 119]).
position41(['uast:Position', 31, 6, 120]).
positions37(['uast:Positions', Start, End]) :- position40(Start), position41(End).
identifier11(['uast:Identifier', 'b', Pos, [Role0]]) :- positions37(Pos),role0(Role0).
object33(Obj) :- value19(Obj), !.
object33(Obj) :- identifier11(Obj), !.
object33(Obj) :- value18(Obj), !.
object33(Obj) :- array41(Obj), !.
object34(Obj) :- object33(Obj), !.
object34(Obj) :- positions34(Obj), !.
object34(Obj) :- array38(Obj), !.
object34(Obj) :- value44(Obj), !.
object34(Obj) :- object31(Obj), !.
object34(Obj) :- object32(Obj), !.
array42([Arg0,Arg1,Arg2]) :- object29(Arg0),object30(Arg1),object34(Arg2).
position42(['uast:Position', 12, 6, 101]).
position43(['uast:Position', 15, 6, 104]).
positions38(['uast:Positions', Start, End]) :- position42(Start), position43(End).
identifier12(['uast:Identifier', 'fib', Pos, [Role0]]) :- positions38(Pos),role0(Role0).
value52('Callee').
array43([Arg0,Arg1]) :- value39(Arg0),value52(Arg1).
object35(Obj) :- value19(Obj), !.
object35(Obj) :- identifier12(Obj), !.
object35(Obj) :- value18(Obj), !.
object35(Obj) :- array43(Obj), !.
array44([]).
positions39(['uast:Positions', Start, _]) :- position42(Start).
object36(Obj) :- array32(Obj), !.
object36(Obj) :- value40(Obj), !.
object36(Obj) :- array42(Obj), !.
object36(Obj) :- object35(Obj), !.
object36(Obj) :- array44(Obj), !.
object36(Obj) :- positions39(Obj), !.
position44(['uast:Position', 5, 6, 94]).
position45(['uast:Position', 11, 6, 100]).
positions40(['uast:Positions', Start, End]) :- position44(Start), position45(End).
array45([Arg0,Arg1]) :- value14(Arg0),value15(Arg1).
object37(Obj) :- value16(Obj), !.
object37(Obj) :- value17(Obj), !.
object37(Obj) :- object36(Obj), !.
object37(Obj) :- positions40(Obj), !.
object37(Obj) :- array45(Obj), !.
block0(['uast:Block', [Stmt0,Stmt1,Stmt2], Pos]) :- positions14(Pos),object14(Stmt0),object25(Stmt1),object37(Stmt2).
positions41(['uast:Positions', _, _]).
function0(['uast:Function', FnType, Body, Pos]) :- function_type0(FnType),block0(Body),positions41(Pos).
positions42(['uast:Positions', _, _]).
identifier13(['uast:Identifier', 'fib', Pos, [Role0]]) :- positions42(Pos),role0(Role0).
alias0(['uast:Alias', Name, Node, Pos]) :- identifier13(Name),function0(Node),positions2(Pos).
function_group0(['uast:FunctionGroup', [Node0,Node1], Pos]) :- positions1(Pos),object1(Node0),alias0(Node1).
array46([Arg0]) :- function_group0(Arg0).
object38(Obj) :- positions0(Obj), !.
object38(Obj) :- array0(Obj), !.
object38(Obj) :- value2(Obj), !.
object38(Obj) :- array46(Obj), !.
% value(Val).
value(X) :- value0(X);value1(X);value2(X);value3(X);value4(X);value5(X);value6(X);value7(X);value8(X);value9(X);value10(X);value11(X);value12(X);value13(X);value14(X);value15(X);value16(X);value17(X);value18(X);value19(X);value20(X);value21(X);value22(X);value23(X);value24(X);value25(X);value26(X);value27(X);value28(X);value29(X);value30(X);value31(X);value32(X);value33(X);value34(X);value35(X);value36(X);value37(X);value38(X);value39(X);value40(X);value41(X);value42(X);value43(X);value44(X);value45(X);value46(X);value47(X);value48(X);value49(X);value50(X);value51(X);value52(X).
% array([Arguments]).
array(X) :- array0(X);array1(X);array2(X);array3(X);array4(X);array5(X);array6(X);array7(X);array8(X);array9(X);array10(X);array11(X);array12(X);array13(X);array14(X);array15(X);array16(X);array17(X);array18(X);array19(X);array20(X);array21(X);array22(X);array23(X);array24(X);array25(X);array26(X);array27(X);array28(X);array29(X);array30(X);array31(X);array32(X);array33(X);array34(X);array35(X);array36(X);array37(X);array38(X);array39(X);array40(X);array41(X);array42(X);array43(X);array44(X);array45(X);array46(X).
% object(Obj).
object(X) :- object0(X);object1(X);object2(X);object3(X);object4(X);object5(X);object6(X);object7(X);object8(X);object9(X);object10(X);object11(X);object12(X);object13(X);object14(X);object15(X);object16(X);object17(X);object18(X);object19(X);object20(X);object21(X);object22(X);object23(X);object24(X);object25(X);object26(X);object27(X);object28(X);object29(X);object30(X);object31(X);object32(X);object33(X);object34(X);object35(X);object36(X);object37(X);object38(X).
% role(Name).
role(X) :- role0(X).
% position([Type, Col, Line, Offset]).
position(X) :- position0(X);position1(X);position2(X);position3(X);position4(X);position5(X);position6(X);position7(X);position8(X);position9(X);position10(X);position11(X);position12(X);position13(X);position14(X);position15(X);position16(X);position17(X);position18(X);position19(X);position20(X);position21(X);position22(X);position23(X);position24(X);position25(X);position26(X);position27(X);position28(X);position29(X);position30(X);position31(X);position32(X);position33(X);position34(X);position35(X);position36(X);position37(X);position38(X);position39(X);position40(X);position41(X);position42(X);position43(X);position44(X);position45(X).
% positions([Type, Start, End]).
positions(X) :- positions0(X);positions1(X);positions2(X);positions3(X);positions4(X);positions5(X);positions6(X);positions7(X);positions8(X);positions9(X);positions10(X);positions11(X);positions12(X);positions13(X);positions14(X);positions15(X);positions16(X);positions17(X);positions18(X);positions19(X);positions20(X);positions21(X);positions22(X);positions23(X);positions24(X);positions25(X);positions26(X);positions27(X);positions28(X);positions29(X);positions30(X);positions31(X);positions32(X);positions33(X);positions34(X);positions35(X);positions36(X);positions37(X);positions38(X);positions39(X);positions40(X);positions41(X);positions42(X).
% identifier([Type, Name, Pos, [Roles]]).
identifier(X) :- identifier0(X);identifier1(X);identifier2(X);identifier3(X);identifier4(X);identifier5(X);identifier6(X);identifier7(X);identifier8(X);identifier9(X);identifier10(X);identifier11(X);identifier12(X);identifier13(X).
% qualified_identifier([Type, [Names], Pos]).
qualified_identifier(_) :- fail.
% comment([Type, Prefix, Suffix, Tab, Text, Block, Pos]).
comment(_) :- fail.
% group([Type, [Nodes], Pos]).
group(_) :- fail.
% function_group([Type, [Nodes], Pos]).
function_group(X) :- function_group0(X).
% block([Type, [Statements], Pos]).
block(X) :- block0(X).
% alias([Type, Name, Node, Pos]).
alias(X) :- alias0(X).
% import([Type, Path, Pos]).
import(_) :- fail.
% runtime_import([Type, Path, Pos]).
runtime_import(_) :- fail.
% runtime_reimport([Type, Path, Pos]).
runtime_reimport(_) :- fail.
% inline_import([Type, Path, Pos]).
inline_import(_) :- fail.
% argument([Type, Name, ArgType, Init, Variadic, MapVariadic, Receiver, Pos]).
argument(X) :- argument0(X);argument1(X);argument2(X);argument3(X).
% function_type([Type, [Arguments], [Returns], Pos]).
function_type(X) :- function_type0(X).
% function([Type, FuncType, Body, Pos]).
function(X) :- function0(X).
```
Next, we can query DB to get all function names and arguments (we can also use any other prolog implementation, e.g. [swi-prolog](https://www.swi-prolog.org)):
```bash
./qpl -f ./examples/python/fib.py.pl -f ./prolog/function.pl -q "function_arg(Fn, Args)."
Fn = fib
Args = [n,a,b]
```
### Example (extract import paths)
For a given `examples/java/Hello.java` file:
```java
// Hello.java
import java.io.*;
import javax.servlet.*;
public class Hello extends GenericServlet {
public void service(final ServletRequest request, final ServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
final PrintWriter pw = response.getWriter();
try {
pw.println("Hello, world!");
} finally {
pw.close();
}
}
}
```
we get following UAST
```
{ '@type': "java:CompilationUnit",
'@role': [File],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 0,
line: 1,
col: 1,
},
end: { '@type': "uast:Position",
offset: 448,
line: 19,
col: 1,
},
},
comments: [
{ '@type': "uast:Comment",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 0,
line: 1,
col: 1,
},
end: { '@type': "uast:Position",
offset: 13,
line: 1,
col: 14,
},
},
Block: false,
Prefix: " ",
Suffix: "",
Tab: "",
Text: "Hello.java",
},
],
imports: [
{ '@type': "uast:Import",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 14,
line: 2,
col: 1,
},
end: { '@type': "uast:Position",
offset: 31,
line: 2,
col: 18,
},
},
All: true,
Names: [],
Path: { '@type': "uast:QualifiedIdentifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 21,
line: 2,
col: 8,
},
end: { '@type': "uast:Position",
offset: 28,
line: 2,
col: 15,
},
},
Names: [
{ '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 21,
line: 2,
col: 8,
},
end: { '@type': "uast:Position",
offset: 25,
line: 2,
col: 12,
},
},
Name: "java",
},
{ '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 26,
line: 2,
col: 13,
},
end: { '@type': "uast:Position",
offset: 28,
line: 2,
col: 15,
},
},
Name: "io",
},
],
},
Target: {
static: "false",
},
},
{ '@type': "uast:Import",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 32,
line: 3,
col: 1,
},
end: { '@type': "uast:Position",
offset: 55,
line: 3,
col: 24,
},
},
All: true,
Names: [],
Path: { '@type': "uast:QualifiedIdentifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 39,
line: 3,
col: 8,
},
end: { '@type': "uast:Position",
offset: 52,
line: 3,
col: 21,
},
},
Names: [
{ '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 39,
line: 3,
col: 8,
},
end: { '@type': "uast:Position",
offset: 44,
line: 3,
col: 13,
},
},
Name: "javax",
},
{ '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 45,
line: 3,
col: 14,
},
end: { '@type': "uast:Position",
offset: 52,
line: 3,
col: 21,
},
},
Name: "servlet",
},
],
},
Target: {
static: "false",
},
},
],
package: ~,
types: [
{ '@type': "java:TypeDeclaration",
'@role': [Declaration, Type, Visibility, World],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 57,
line: 5,
col: 1,
},
end: { '@type': "uast:Position",
offset: 445,
line: 16,
col: 2,
},
},
bodyDeclarations: [
{ '@type': "uast:FunctionGroup",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 105,
line: 6,
col: 5,
},
end: { '@type': "uast:Position",
offset: 443,
line: 15,
col: 6,
},
},
Nodes: [
~,
[
{ '@type': "java:Modifier",
'@token': "public",
'@role': [Visibility, World],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 105,
line: 6,
col: 5,
},
end: { '@type': "uast:Position",
offset: 111,
line: 6,
col: 11,
},
},
},
],
{ '@type': "uast:Alias",
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 117,
line: 6,
col: 17,
},
end: { '@type': "uast:Position",
offset: 124,
line: 6,
col: 24,
},
},
Name: "service",
},
Node: { '@type': "uast:Function",
Body: { '@type': "uast:Block",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 228,
line: 7,
col: 42,
},
end: { '@type': "uast:Position",
offset: 443,
line: 15,
col: 6,
},
},
Statements: [
{ '@type': "java:ExpressionStatement",
'@role': [Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 238,
line: 8,
col: 9,
},
end: { '@type': "uast:Position",
offset: 275,
line: 8,
col: 46,
},
},
expression: { '@type': "java:MethodInvocation",
'@role': [Call, Expression],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 238,
line: 8,
col: 9,
},
end: { '@type': "uast:Position",
offset: 274,
line: 8,
col: 45,
},
},
arguments: [
{ '@type': "uast:String",
'@role': [Argument, Call, Positional],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 262,
line: 8,
col: 33,
},
end: { '@type': "uast:Position",
offset: 273,
line: 8,
col: 44,
},
},
Format: "",
Value: "text/html",
},
],
expression: { '@type': "uast:Identifier",
'@role': [Call, Receiver],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 238,
line: 8,
col: 9,
},
end: { '@type': "uast:Position",
offset: 246,
line: 8,
col: 17,
},
},
Name: "response",
},
name: { '@type': "uast:Identifier",
'@role': [Call, Callee],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 247,
line: 8,
col: 18,
},
end: { '@type': "uast:Position",
offset: 261,
line: 8,
col: 32,
},
},
Name: "setContentType",
},
typeArguments: ~,
},
},
{ '@type': "java:VariableDeclarationStatement",
'@role': [Declaration, Statement, Variable],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 284,
line: 9,
col: 9,
},
end: { '@type': "uast:Position",
offset: 328,
line: 9,
col: 53,
},
},
fragments: [
{ '@type': "java:VariableDeclarationFragment",
'@role': [Declaration, Variable],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 302,
line: 9,
col: 27,
},
end: { '@type': "uast:Position",
offset: 327,
line: 9,
col: 52,
},
},
'extraDimensions2': ~,
initializer: { '@type': "java:MethodInvocation",
'@role': [Call, Expression],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 307,
line: 9,
col: 32,
},
end: { '@type': "uast:Position",
offset: 327,
line: 9,
col: 52,
},
},
arguments: ~,
expression: { '@type': "uast:Identifier",
'@role': [Call, Receiver],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 307,
line: 9,
col: 32,
},
end: { '@type': "uast:Position",
offset: 315,
line: 9,
col: 40,
},
},
Name: "response",
},
name: { '@type': "uast:Identifier",
'@role': [Call, Callee],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 316,
line: 9,
col: 41,
},
end: { '@type': "uast:Position",
offset: 325,
line: 9,
col: 50,
},
},
Name: "getWriter",
},
typeArguments: ~,
},
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 302,
line: 9,
col: 27,
},
end: { '@type': "uast:Position",
offset: 304,
line: 9,
col: 29,
},
},
Name: "pw",
},
},
],
modifiers: [
{ '@type': "java:Modifier",
'@token': "final",
'@role': [Incomplete],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 284,
line: 9,
col: 9,
},
end: { '@type': "uast:Position",
offset: 289,
line: 9,
col: 14,
},
},
},
],
type: { '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 290,
line: 9,
col: 15,
},
end: { '@type': "uast:Position",
offset: 301,
line: 9,
col: 26,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 290,
line: 9,
col: 15,
},
end: { '@type': "uast:Position",
offset: 301,
line: 9,
col: 26,
},
},
Name: "PrintWriter",
},
},
},
{ '@type': "java:TryStatement",
'@role': [Statement, Try],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 337,
line: 10,
col: 9,
},
end: { '@type': "uast:Position",
offset: 437,
line: 14,
col: 10,
},
},
body: { '@type': "uast:Block",
'@role': [Body, Try],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 341,
line: 10,
col: 13,
},
end: { '@type': "uast:Position",
offset: 393,
line: 12,
col: 10,
},
},
Statements: [
{ '@type': "java:ExpressionStatement",
'@role': [Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 355,
line: 11,
col: 13,
},
end: { '@type': "uast:Position",
offset: 383,
line: 11,
col: 41,
},
},
expression: { '@type': "java:MethodInvocation",
'@role': [Call, Expression],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 355,
line: 11,
col: 13,
},
end: { '@type': "uast:Position",
offset: 382,
line: 11,
col: 40,
},
},
arguments: [
{ '@type': "uast:String",
'@role': [Argument, Call, Positional],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 366,
line: 11,
col: 24,
},
end: { '@type': "uast:Position",
offset: 381,
line: 11,
col: 39,
},
},
Format: "",
Value: "Hello, world!",
},
],
expression: { '@type': "uast:Identifier",
'@role': [Call, Receiver],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 355,
line: 11,
col: 13,
},
end: { '@type': "uast:Position",
offset: 357,
line: 11,
col: 15,
},
},
Name: "pw",
},
name: { '@type': "uast:Identifier",
'@role': [Call, Callee],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 358,
line: 11,
col: 16,
},
end: { '@type': "uast:Position",
offset: 365,
line: 11,
col: 23,
},
},
Name: "println",
},
typeArguments: ~,
},
},
],
},
catchClauses: ~,
finally: { '@type': "uast:Block",
'@role': [Finally, Try],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 402,
line: 12,
col: 19,
},
end: { '@type': "uast:Position",
offset: 437,
line: 14,
col: 10,
},
},
Statements: [
{ '@type': "java:ExpressionStatement",
'@role': [Statement],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 416,
line: 13,
col: 13,
},
end: { '@type': "uast:Position",
offset: 427,
line: 13,
col: 24,
},
},
expression: { '@type': "java:MethodInvocation",
'@role': [Call, Expression],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 416,
line: 13,
col: 13,
},
end: { '@type': "uast:Position",
offset: 426,
line: 13,
col: 23,
},
},
arguments: ~,
expression: { '@type': "uast:Identifier",
'@role': [Call, Receiver],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 416,
line: 13,
col: 13,
},
end: { '@type': "uast:Position",
offset: 418,
line: 13,
col: 15,
},
},
Name: "pw",
},
name: { '@type': "uast:Identifier",
'@role': [Call, Callee],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 419,
line: 13,
col: 16,
},
end: { '@type': "uast:Position",
offset: 424,
line: 13,
col: 21,
},
},
Name: "close",
},
typeArguments: ~,
},
},
],
},
resources: ~,
},
],
},
Type: { '@type': "uast:FunctionType",
Arguments: [
{ '@type': "uast:Argument",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 125,
line: 6,
col: 25,
},
end: { '@type': "uast:Position",
offset: 153,
line: 6,
col: 53,
},
},
Init: ~,
MapVariadic: false,
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 146,
line: 6,
col: 46,
},
end: { '@type': "uast:Position",
offset: 153,
line: 6,
col: 53,
},
},
Name: "request",
},
Receiver: false,
Type: { '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 131,
line: 6,
col: 31,
},
end: { '@type': "uast:Position",
offset: 145,
line: 6,
col: 45,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 131,
line: 6,
col: 31,
},
end: { '@type': "uast:Position",
offset: 145,
line: 6,
col: 45,
},
},
Name: "ServletRequest",
},
},
Variadic: false,
},
{ '@type': "uast:Argument",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 155,
line: 6,
col: 55,
},
end: { '@type': "uast:Position",
offset: 185,
line: 6,
col: 85,
},
},
Init: ~,
MapVariadic: false,
Name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 177,
line: 6,
col: 77,
},
end: { '@type': "uast:Position",
offset: 185,
line: 6,
col: 85,
},
},
Name: "response",
},
Receiver: false,
Type: { '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 161,
line: 6,
col: 61,
},
end: { '@type': "uast:Position",
offset: 176,
line: 6,
col: 76,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 161,
line: 6,
col: 61,
},
end: { '@type': "uast:Position",
offset: 176,
line: 6,
col: 76,
},
},
Name: "ServletResponse",
},
},
Variadic: false,
},
],
Returns: ~,
},
},
},
{
constructor: "false",
thrownExceptionTypes: [
{ '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 198,
line: 7,
col: 12,
},
end: { '@type': "uast:Position",
offset: 214,
line: 7,
col: 28,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 198,
line: 7,
col: 12,
},
end: { '@type': "uast:Position",
offset: 214,
line: 7,
col: 28,
},
},
Name: "ServletException",
},
},
{ '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 216,
line: 7,
col: 30,
},
end: { '@type': "uast:Position",
offset: 227,
line: 7,
col: 41,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 216,
line: 7,
col: 30,
},
end: { '@type': "uast:Position",
offset: 227,
line: 7,
col: 41,
},
},
Name: "IOException",
},
},
],
typeParameters: ~,
},
],
},
],
interface: "false",
javadoc: ~,
modifiers: [
{ '@type': "java:Modifier",
'@token': "public",
'@role': [Visibility, World],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 57,
line: 5,
col: 1,
},
end: { '@type': "uast:Position",
offset: 63,
line: 5,
col: 7,
},
},
},
],
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 70,
line: 5,
col: 14,
},
end: { '@type': "uast:Position",
offset: 75,
line: 5,
col: 19,
},
},
Name: "Hello",
},
superInterfaceTypes: ~,
superclassType: { '@type': "java:SimpleType",
'@role': [Type],
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 84,
line: 5,
col: 28,
},
end: { '@type': "uast:Position",
offset: 98,
line: 5,
col: 42,
},
},
annotations: ~,
name: { '@type': "uast:Identifier",
'@pos': { '@type': "uast:Positions",
start: { '@type': "uast:Position",
offset: 84,
line: 5,
col: 28,
},
end: { '@type': "uast:Position",
offset: 98,
line: 5,
col: 42,
},
},
Name: "GenericServlet",
},
},
typeParameters: ~,
},
],
}
```
what can be transformed into a prolog program
```prolog
value0('Visibility').
val