Zig 0.17.0-dev (Split by item)

Shortcut keys
?
Show these tips
S
Focus search field
Esc
Clear focus & close tips
U
Jump to source code
↑
Move up in search results
↓
Move down in search results
↵
Go to active search result
This is an example of documentation generated by ZigDoc, an alternative to Zig's built-in Auto Doc feature. See also examples in other modes/formats. The project being documented here (as the example) is the Zig standard library. Public Namespace

dynamic

Public Namespace

Structs

Types

Values

Functions

pub fn isNumberFormattedLikeAnInteger(value: []const u8) bool

For the slice you get from a Token.number or Token.allocated_number, this function returns true if the number doesn't contain any fraction or exponent components, and is not -0. Note, the numeric value encoded by the value may still be an integer, such as 1.0. This function is meant to give a hint about whether integer parsing or float parsing should be used on the value. This function will not give meaningful results on non-numeric input.

fn handleCompleteValue(stack: *Array, allocator: Allocator, source: anytype, value_: Value, options: ParseOptions) !?Value

File

json/dynamic.zig
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
const std = @import("std");
const debug = std.debug;
const ArenaAllocator = std.heap.ArenaAllocator;
const StringArrayHashMap = std.array_hash_map.String;
const Allocator = std.mem.Allocator;
const json = std.json;

const ParseOptions = @import("./static.zig").ParseOptions;
const ParseError = @import("./static.zig").ParseError;

const isNumberFormattedLikeAnInteger = @import("Scanner.zig").isNumberFormattedLikeAnInteger;

pub const ObjectMap = StringArrayHashMap(Value);
pub const Array = std.array_list.Managed(Value);

/// Represents any JSON value, potentially containing other JSON values.
/// A .float value may be an approximation of the original value.
/// Arbitrary precision numbers can be represented by .number_string values.
/// See also `std.json.ParseOptions.parse_numbers`.
pub const Value = union(enum) {
    null,
    bool: bool,
    integer: i64,
    float: f64,
    number_string: []const u8,
    string: []const u8,
    array: Array,
    object: ObjectMap,

    pub fn parseFromNumberSlice(s: []const u8) Value {
        if (!isNumberFormattedLikeAnInteger(s)) {
            const f = std.fmt.parseFloat(f64, s) catch unreachable;
            if (std.math.isFinite(f)) {
                return Value{ .float = f };
            } else {
                return Value{ .number_string = s };
            }
        }
        if (std.fmt.parseInt(i64, s, 10)) |i| {
            return Value{ .integer = i };
        } else |e| {
            switch (e) {
                error.Overflow => return Value{ .number_string = s },
                error.InvalidCharacter => unreachable,
            }
        }
    }

    pub fn dump(v: Value) void {
        const stderr = std.debug.lockStderr(&.{});
        defer std.debug.unlockStderr();
        json.Stringify.value(v, .{}, &stderr.file_writer.interface) catch return;
    }

    pub fn jsonStringify(value: @This(), jws: anytype) !void {
        switch (value) {
            .null => try jws.write(null),
            .bool => |inner| try jws.write(inner),
            .integer => |inner| try jws.write(inner),
            .float => |inner| try jws.write(inner),
            .number_string => |inner| try jws.print("{s}", .{inner}),
            .string => |inner| try jws.write(inner),
            .array => |inner| try jws.write(inner.items),
            .object => |inner| {
                try jws.beginObject();
                var it = inner.iterator();
                while (it.next()) |entry| {
                    try jws.objectField(entry.key_ptr.*);
                    try jws.write(entry.value_ptr.*);
                }
                try jws.endObject();
            },
        }
    }

    pub fn jsonParse(allocator: Allocator, source: anytype, options: ParseOptions) ParseError(@TypeOf(source.*))!@This() {
        // The grammar of the stack is:
        //  (.array | .object .string)*
        var stack = Array.init(allocator);
        defer stack.deinit();

        while (true) {
            // Assert the stack grammar at the top of the stack.
            debug.assert(stack.items.len == 0 or
                stack.items[stack.items.len - 1] == .array or
                (stack.items[stack.items.len - 2] == .object and stack.items[stack.items.len - 1] == .string));

            switch (try source.nextAllocMax(allocator, .alloc_always, options.max_value_len.?)) {
                .allocated_string => |s| {
                    return try handleCompleteValue(&stack, allocator, source, Value{ .string = s }, options) orelse continue;
                },
                .allocated_number => |slice| {
                    if (options.parse_numbers) {
                        return try handleCompleteValue(&stack, allocator, source, Value.parseFromNumberSlice(slice), options) orelse continue;
                    } else {
                        return try handleCompleteValue(&stack, allocator, source, Value{ .number_string = slice }, options) orelse continue;
                    }
                },

                .null => return try handleCompleteValue(&stack, allocator, source, .null, options) orelse continue,
                .true => return try handleCompleteValue(&stack, allocator, source, Value{ .bool = true }, options) orelse continue,
                .false => return try handleCompleteValue(&stack, allocator, source, Value{ .bool = false }, options) orelse continue,

                .object_begin => {
                    switch (try source.nextAllocMax(allocator, .alloc_always, options.max_value_len.?)) {
                        .object_end => return try handleCompleteValue(&stack, allocator, source, Value{ .object = .empty }, options) orelse continue,
                        .allocated_string => |key| {
                            try stack.appendSlice(&[_]Value{
                                Value{ .object = .empty },
                                Value{ .string = key },
                            });
                        },
                        else => unreachable,
                    }
                },
                .array_begin => {
                    try stack.append(Value{ .array = Array.init(allocator) });
                },
                .array_end => return try handleCompleteValue(&stack, allocator, source, stack.pop().?, options) orelse continue,

                else => unreachable,
            }
        }
    }

    pub fn jsonParseFromValue(allocator: Allocator, source: Value, options: ParseOptions) !@This() {
        _ = allocator;
        _ = options;
        return source;
    }
};

fn handleCompleteValue(stack: *Array, allocator: Allocator, source: anytype, value_: Value, options: ParseOptions) !?Value {
    if (stack.items.len == 0) return value_;
    var value = value_;
    while (true) {
        // Assert the stack grammar at the top of the stack.
        debug.assert(stack.items[stack.items.len - 1] == .array or
            (stack.items[stack.items.len - 2] == .object and stack.items[stack.items.len - 1] == .string));
        switch (stack.items[stack.items.len - 1]) {
            .string => |key| {
                // stack: [..., .object, .string]
                _ = stack.pop();

                // stack: [..., .object]
                var object = &stack.items[stack.items.len - 1].object;

                const gop = try object.getOrPut(allocator, key);
                if (gop.found_existing) {
                    switch (options.duplicate_field_behavior) {
                        .use_first => {},
                        .@"error" => return error.DuplicateField,
                        .use_last => {
                            gop.value_ptr.* = value;
                        },
                    }
                } else {
                    gop.value_ptr.* = value;
                }

                // This is an invalid state to leave the stack in,
                // so we have to process the next token before we return.
                switch (try source.nextAllocMax(allocator, .alloc_always, options.max_value_len.?)) {
                    .object_end => {
                        // This object is complete.
                        value = stack.pop().?;
                        // Effectively recurse now that we have a complete value.
                        if (stack.items.len == 0) return value;
                        continue;
                    },
                    .allocated_string => |next_key| {
                        // We've got another key.
                        try stack.append(Value{ .string = next_key });
                        // stack: [..., .object, .string]
                        return null;
                    },
                    else => unreachable,
                }
            },
            .array => |*array| {
                // stack: [..., .array]
                try array.append(value);
                return null;
            },
            else => unreachable,
        }
    }
}

test {
    _ = @import("dynamic_test.zig");
}