aboutsummaryrefslogtreecommitdiff
path: root/v_windows/v/old/vlib/x/json2/decoder.v
diff options
context:
space:
mode:
authorIndrajith K L2022-12-03 17:00:20 +0530
committerIndrajith K L2022-12-03 17:00:20 +0530
commitf5c4671bfbad96bf346bd7e9a21fc4317b4959df (patch)
tree2764fc62da58f2ba8da7ed341643fc359873142f /v_windows/v/old/vlib/x/json2/decoder.v
downloadcli-tools-windows-master.tar.gz
cli-tools-windows-master.tar.bz2
cli-tools-windows-master.zip
Adds most of the toolsHEADmaster
Diffstat (limited to 'v_windows/v/old/vlib/x/json2/decoder.v')
-rw-r--r--v_windows/v/old/vlib/x/json2/decoder.v200
1 files changed, 200 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/x/json2/decoder.v b/v_windows/v/old/vlib/x/json2/decoder.v
new file mode 100644
index 0000000..a45a091
--- /dev/null
+++ b/v_windows/v/old/vlib/x/json2/decoder.v
@@ -0,0 +1,200 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module json2
+
+// `Any` is a sum type that lists the possible types to be decoded and used.
+pub type Any = Null | []Any | bool | f32 | f64 | i64 | int | map[string]Any | string |
+ u64
+
+// `Null` struct is a simple representation of the `null` value in JSON.
+pub struct Null {
+ is_null bool = true
+}
+
+struct Parser {
+mut:
+ scanner &Scanner
+ p_tok Token
+ tok Token
+ n_tok Token
+ n_level int
+ convert_type bool = true
+}
+
+struct InvalidTokenError {
+ msg string
+ code int
+}
+
+struct UnknownTokenError {
+ msg string
+ code int
+}
+
+fn (mut p Parser) next() {
+ p.p_tok = p.tok
+ p.tok = p.n_tok
+ p.n_tok = p.scanner.scan()
+}
+
+fn (mut p Parser) next_with_err() ? {
+ p.next()
+ if p.tok.kind == .error {
+ return error(p.emit_error(p.tok.lit.bytestr()))
+ }
+}
+
+fn (p Parser) emit_error(msg string) string {
+ line := p.tok.line
+ column := p.tok.col + p.tok.lit.len
+ return '[x.json2] $msg ($line:$column)'
+}
+
+// TODO: copied from v.util to avoid the entire module and its functions
+// from being imported. remove later once -skip-unused is enabled by default.
+fn skip_bom(file_content string) string {
+ mut raw_text := file_content
+ // BOM check
+ if raw_text.len >= 3 {
+ unsafe {
+ c_text := raw_text.str
+ if c_text[0] == 0xEF && c_text[1] == 0xBB && c_text[2] == 0xBF {
+ // skip three BOM bytes
+ offset_from_begin := 3
+ raw_text = tos(c_text[offset_from_begin], vstrlen(c_text) - offset_from_begin)
+ }
+ }
+ }
+ return raw_text
+}
+
+fn new_parser(srce string, convert_type bool) Parser {
+ src := skip_bom(srce)
+ return Parser{
+ scanner: &Scanner{
+ text: src.bytes()
+ }
+ convert_type: convert_type
+ }
+}
+
+fn (mut p Parser) decode() ?Any {
+ p.next()
+ p.next_with_err() ?
+ fi := p.decode_value() ?
+ if p.tok.kind != .eof {
+ return IError(&InvalidTokenError{
+ msg: p.emit_error('invalid token `$p.tok.kind`')
+ })
+ }
+ return fi
+}
+
+fn (mut p Parser) decode_value() ?Any {
+ if p.n_level + 1 == 500 {
+ return error(p.emit_error('reached maximum nesting level of 500'))
+ }
+ match p.tok.kind {
+ .lsbr {
+ return p.decode_array()
+ }
+ .lcbr {
+ return p.decode_object()
+ }
+ .int_, .float {
+ tl := p.tok.lit.bytestr()
+ kind := p.tok.kind
+ p.next_with_err() ?
+ if p.convert_type {
+ if kind == .float {
+ return Any(tl.f64())
+ }
+ return Any(tl.i64())
+ }
+ return Any(tl)
+ }
+ .bool_ {
+ lit := p.tok.lit.bytestr()
+ p.next_with_err() ?
+ if p.convert_type {
+ return Any(lit.bool())
+ }
+ return Any(lit)
+ }
+ .null {
+ p.next_with_err() ?
+ if p.convert_type {
+ return Any(null)
+ }
+ return Any('null')
+ }
+ .str_ {
+ str := p.tok.lit.bytestr()
+ p.next_with_err() ?
+ return Any(str)
+ }
+ else {
+ return IError(&InvalidTokenError{
+ msg: p.emit_error('invalid token `$p.tok.kind`')
+ })
+ }
+ }
+ return Any(null)
+}
+
+fn (mut p Parser) decode_array() ?Any {
+ mut items := []Any{}
+ p.next_with_err() ?
+ p.n_level++
+ for p.tok.kind != .rsbr {
+ item := p.decode_value() ?
+ items << item
+ if p.tok.kind == .comma {
+ p.next_with_err() ?
+ if p.tok.kind == .rsbr || p.tok.kind == .rcbr {
+ return IError(&InvalidTokenError{
+ msg: p.emit_error('invalid token `$p.tok.lit')
+ })
+ }
+ } else if p.tok.kind == .rsbr {
+ break
+ } else {
+ return IError(&UnknownTokenError{
+ msg: p.emit_error("unknown token '$p.tok.lit' when decoding array.")
+ })
+ }
+ }
+ p.next_with_err() ?
+ p.n_level--
+ return Any(items)
+}
+
+fn (mut p Parser) decode_object() ?Any {
+ mut fields := map[string]Any{}
+ p.next_with_err() ?
+ p.n_level++
+ for p.tok.kind != .rcbr {
+ is_key := p.tok.kind == .str_ && p.n_tok.kind == .colon
+ if !is_key {
+ return IError(&InvalidTokenError{
+ msg: p.emit_error('invalid token `$p.tok.kind`, expecting `str_`')
+ })
+ }
+ cur_key := p.tok.lit.bytestr()
+ p.next_with_err() ?
+ p.next_with_err() ?
+ fields[cur_key] = p.decode_value() ?
+ if p.tok.kind == .comma {
+ p.next_with_err() ?
+ if p.tok.kind != .str_ {
+ return IError(&UnknownTokenError{
+ msg: p.emit_error("unknown token '$p.tok.lit' when decoding object.")
+ })
+ }
+ }
+ }
+ p.next_with_err() ?
+ p.n_level--
+ return Any(fields)
+}