private import json_parser
private import json_lexer
+# Something that can be translated to JSON.
+interface Jsonable
+ # Encode `self` in JSON.
+ fun to_json: String is abstract
+end
+
+redef class Text
+ super Jsonable
+
+ # Encode `self` in JSON.
+ #
+ # assert "\t\"http://example.com\"\r\n\0\\".to_json ==
+ # "\"\\t\\\"http:\\/\\/example.com\\\"\\r\\n\\u0000\\\\\""
+ redef fun to_json do
+ var buffer = new FlatBuffer
+ buffer.add '\"'
+ for i in [0..self.length[ do
+ var char = self[i]
+ if char == '\\' then
+ buffer.append "\\\\"
+ else if char == '\"' then
+ buffer.append "\\\""
+ else if char == '\/' then
+ buffer.append "\\/"
+ else if char < 16.ascii then
+ if char == '\n' then
+ buffer.append "\\n"
+ else if char == '\r' then
+ buffer.append "\\r"
+ else if char == '\t' then
+ buffer.append "\\t"
+ else if char == 0x0C.ascii then
+ buffer.append "\\f"
+ else if char == 0x08.ascii then
+ buffer.append "\\b"
+ else
+ buffer.append "\\u000{char.ascii.to_hex}"
+ end
+ else if char < ' ' then
+ buffer.append "\\u00{char.ascii.to_hex}"
+ else
+ buffer.add char
+ end
+ end
+ buffer.add '\"'
+ return buffer.write_to_string
+ end
+
+ fun json_to_nit_object: nullable Object
+ do
+ var lexer = new Lexer_json(to_s)
+ var parser = new Parser_json
+ var tokens = lexer.lex
+ parser.tokens.add_all(tokens)
+ var root_node = parser.parse
+ if root_node isa NStart then
+ return root_node.n_0.to_nit_object
+ else if root_node isa NLexerError then
+ var pos = root_node.position
+ print "Json lexer error: {root_node.message} at {pos or else "<unknown>"} for {root_node}"
+ return null
+ else if root_node isa NParserError then
+ var pos = root_node.position
+ print "Json parsing error: {root_node.message} at {pos or else "<unknown>"} for {root_node}"
+ return null
+ else abort
+ end
+end
+
+redef class Buffer
+
+ # Append the JSON representation of `jsonable` to `self`.
+ #
+ # Append `"null"` for `null`.
+ private fun append_json_of(jsonable: nullable Jsonable) do
+ if jsonable isa Jsonable then
+ append jsonable.to_json
+ else
+ append "null"
+ end
+ end
+end
+
+redef class Int
+ super Jsonable
+
+ # Encode `self` in JSON.
+ #
+ # assert 0.to_json == "0"
+ # assert (-42).to_json == "-42"
+ redef fun to_json do return self.to_s
+end
+
+redef class Float
+ super Jsonable
+
+ # Encode `self` in JSON.
+ #
+ # Note: Because this method use `to_s`, it may lose precision.
+ #
+ # ~~~
+ # # Will not work as expected.
+ # # assert (-0.0).to_json == "-0.0"
+ #
+ # assert (.5).to_json == "0.5"
+ # assert (0.0).to_json == "0.0"
+ # ~~~
+ redef fun to_json do return self.to_s
+end
+
+redef class Bool
+ super Jsonable
+
+ # Encode `self` in JSON.
+ #
+ # assert true.to_json == "true"
+ # assert false.to_json == "false"
+ redef fun to_json do return self.to_s
+end
+
+# A map that can be translated into a JSON object.
+interface JsonMapRead[K: String, V: nullable Jsonable]
+ super MapRead[K, V]
+ super Jsonable
+
+ # Encode `self` in JSON.
+ #
+ # var obj = new JsonObject
+ # obj["foo"] = "bar"
+ # assert obj.to_json == "\{\"foo\":\"bar\"\}"
+ # obj = new JsonObject
+ # obj["baz"] = null
+ # assert obj.to_json == "\{\"baz\":null\}"
+ redef fun to_json do
+ var buffer = new FlatBuffer
+ buffer.append "\{"
+ var it = iterator
+ if it.is_ok then
+ append_json_entry(it, buffer)
+ while it.is_ok do
+ buffer.append ","
+ append_json_entry(it, buffer)
+ end
+ end
+ it.finish
+ buffer.append "\}"
+ return buffer.write_to_string
+ end
+
+ private fun append_json_entry(iterator: MapIterator[String, nullable Jsonable],
+ buffer: Buffer) do
+ buffer.append iterator.key.to_json
+ buffer.append ":"
+ buffer.append_json_of(iterator.item)
+ iterator.next
+ end
+end
+
+# A JSON Object.
+class JsonObject
+ super JsonMapRead[String, nullable Jsonable]
+ super HashMap[String, nullable Jsonable]
+end
+
+# A sequence that can be translated into a JSON array.
+class JsonSequenceRead[E: nullable Jsonable]
+ super Jsonable
+ super SequenceRead[E]
+
+ # Encode `self` in JSON.
+ #
+ # var arr = new JsonArray.with_items("foo", null)
+ # assert arr.to_json == "[\"foo\",null]"
+ # arr.pop
+ # assert arr.to_json =="[\"foo\"]"
+ # arr.pop
+ # assert arr.to_json =="[]"
+ redef fun to_json do
+ var buffer = new FlatBuffer
+ buffer.append "["
+ var it = iterator
+ if it.is_ok then
+ append_json_entry(it, buffer)
+ while it.is_ok do
+ buffer.append ","
+ append_json_entry(it, buffer)
+ end
+ end
+ it.finish
+ buffer.append "]"
+ return buffer.write_to_string
+ end
+
+ private fun append_json_entry(iterator: Iterator[nullable Jsonable],
+ buffer: Buffer) do
+ buffer.append_json_of(iterator.item)
+ iterator.next
+ end
+end
+
+# A JSON array.
+class JsonArray
+ super JsonSequenceRead[nullable Jsonable]
+ super Array[nullable Jsonable]
+end
+
+################################################################################
+# Redef parser
+
redef class Nvalue
fun to_nit_object: nullable Object is abstract
end
redef class Nelements_head
redef fun items do return [n_value]
end
-
-redef class Text
- fun json_to_nit_object: nullable Object
- do
- var lexer = new Lexer_json(to_s)
- var parser = new Parser_json
- var tokens = lexer.lex
- parser.tokens.add_all(tokens)
- var root_node = parser.parse
- if root_node isa NStart then
- return root_node.n_0.to_nit_object
- else if root_node isa NLexerError then
- var pos = root_node.position
- print "Json lexer error: {root_node.message} at {pos or else "<unknown>"} for {root_node}"
- return null
- else if root_node isa NParserError then
- var pos = root_node.position
- print "Json parsing error: {root_node.message} at {pos or else "<unknown>"} for {root_node}"
- return null
- else abort
- end
-end
nitlanguage / nit.git / commitdiff