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
194
195
196
197
198
199
200
201
202
203
|
#pragma once
#include "string_builder.h"
namespace NYT {
////////////////////////////////////////////////////////////////////////////////
/*
* Format: a type-safe and fast formatting utility.
*
* Basically works as a type-safe analogue of |sprintf| and is expected to
* be backwards-compatible with the latter.
*
* Like Go's |Sprintf|, supports the ultimate format specifier |v|
* causing arguments to be emitted in default format.
* This is the default and preferred way of formatting things,
* which should be used in newer code.
*
* |Format| may currently invoke |sprintf| internally for emitting numeric and some other
* types. You can always write your own optimized implementation, if you wish :)
*
* In additional to the usual |sprintf|, supports a number of non-standard flags:
*
* |q| Causes the argument to be surrounded with single quotes (|'|).
* Applies to all types.
*
* |Q| Causes the argument to be surrounded with double quotes (|"|).
* Applies to all types.
*
* |l| The argument is emitted in "lowercase" style.
* Only applies to enums and bools.
*
* The following argument types are supported:
*
* Strings (including |const char*|, |TStringBuf|, and |TString|) and chars:
* Emitted as is. Fast.
*
* Numerics and pointers:
* Emitted using |sprintf|. Maybe not that fast.
*
* |bool|:
* Emitted either as |True| and |False| or |true| and |false| (if lowercase mode is ON).
*
* Enums:
* Emitted in either camel (|SomeName|) or in lowercase-with-underscores style
* (|some_name|, if lowercase mode is ON).
*
* Nullables:
* |std::nullopt| is emitted as |<null>|.
*
* All others:
* Emitted as strings by calling |ToString|.
*
*/
template <class... TArgs>
void Format(TStringBuilderBase* builder, TStaticFormat<TArgs...> format, TArgs&&... args);
template <class... TArgs>
void Format(TStringBuilderBase* builder, TRuntimeFormat format, TArgs&&... args);
template <class... TArgs>
TString Format(TStaticFormat<TArgs...> format, TArgs&&... args);
template <class... TArgs>
TString Format(TRuntimeFormat format, TArgs&&... args);
////////////////////////////////////////////////////////////////////////////////
template <class TRange, class TFormatter>
struct TFormattableView
{
using TBegin = std::decay_t<decltype(std::declval<const TRange>().begin())>;
using TEnd = std::decay_t<decltype(std::declval<const TRange>().end())>;
TBegin RangeBegin;
TEnd RangeEnd;
TFormatter Formatter;
size_t Limit = std::numeric_limits<size_t>::max();
TBegin begin() const;
TEnd end() const;
};
//! Annotates a given #range with #formatter to be applied to each item.
template <class TRange, class TFormatter>
TFormattableView<TRange, TFormatter> MakeFormattableView(
const TRange& range,
TFormatter&& formatter);
template <class TRange, class TFormatter>
TFormattableView<TRange, TFormatter> MakeShrunkFormattableView(
const TRange& range,
TFormatter&& formatter,
size_t limit);
////////////////////////////////////////////////////////////////////////////////
template <class TFormatter>
struct TFormatterWrapper
{
TFormatter Formatter;
};
// Allows insertion of text conditionally.
// Usage:
/*
NYT::Format(
"Value is %v%v",
42,
MakeFormatterWrapper([&] (auto* builder) {
If (PossiblyMissingInfo_) {
builder->AppendString(", PossiblyMissingInfo: ");
FormatValue(builder, PossiblyMissingInfo_, "v");
}
}));
*/
template <class TFormatter>
TFormatterWrapper<TFormatter> MakeFormatterWrapper(
TFormatter&& formatter);
////////////////////////////////////////////////////////////////////////////////
template <class... TArgs>
class TLazyMultiValueFormatter;
template <class... TArgs>
void FormatValue(
TStringBuilderBase* builder,
const TLazyMultiValueFormatter<TArgs...>& value,
TStringBuf /*spec*/);
//! A wrapper for a bunch of values that formats them lazily on demand.
/*!
* The intended use of this class is when you need to use the same formatted string
* in several places in the function (e.g. log message tags) and want both to avoid
* code duplication and premature formatting of the values until necessary.
*
* NB: lvalues are captured by reference without lifetime extension.
*/
template <class... TArgs>
class TLazyMultiValueFormatter
: private TNonCopyable
{
public:
TLazyMultiValueFormatter(TStringBuf format, TArgs&&... args);
// NB(arkady-e1ppa): We actually have to
// forward declare this method as above
// and friend-declare it as specialization
// here because clang is stupid and would
// treat this friend declartion as a hidden friend
// declaration which in turn is treated as a separate symbol
// causing linker to not find the actual definition.
friend void FormatValue<>(
TStringBuilderBase* builder,
const TLazyMultiValueFormatter& value,
TStringBuf /*spec*/);
private:
const TStringBuf Format_;
const std::tuple<TArgs...> Args_;
};
template <class ... Args>
auto MakeLazyMultiValueFormatter(TStringBuf format, Args&&... args);
////////////////////////////////////////////////////////////////////////////////
/*
Example:
FormatVector("One: %v, Two: %v, Three: %v", {1, 2, 3})
=> "One: 1, Two: 2, Three: 3"
*/
template <size_t Length, class TVector>
void FormatVector(
TStringBuilderBase* builder,
const char (&format)[Length],
const TVector& vec);
template <class TVector>
void FormatVector(
TStringBuilderBase* builder,
TStringBuf format,
const TVector& vec);
template <size_t Length, class TVector>
TString FormatVector(
const char (&format)[Length],
const TVector& vec);
template <class TVector>
TString FormatVector(
TStringBuf format,
const TVector& vec);
////////////////////////////////////////////////////////////////////////////////
} // namespace NYT
#define FORMAT_INL_H_
#include "format-inl.h"
#undef FORMAT_INL_H_
|
