Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Octocat-spinner-32-eaf2f5

Cannot retrieve contributors at this time

file 297 lines (257 sloc) 12.609 kb
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296
#ifndef _STRINGF_H
#define _STRINGF_H

#include "libs.h"
#include <string>
#include <SDL_stdinc.h>

// provides (for integer types, floating point types, const char* and std::string):
//
// Basic value -> string functions:
// std::string to_string(T value);
// std::string to_string(T value, const FormatSpec& format);
//
// You may extend the system by providing your own overloads for
// std::string to_string(T value, const FormatSpec& format)
//
// String formatter:
// std::string stringf(const char* fmt, ...);
//
// This should work for up to 7 arguments, where each argument is:
// - An object of type FormatArg or FormatArgT<T> for some T
// - Or, the result of a call to formatarg(name, value)
// - Or, a value of a type that can be converted to a string with to_string
//
// formatarg() allows you to give a name and optionally a default format
// for an argument to stringf()
// e.g., formatarg("distance", 42.5, "f.2")
//
// That argument can then be referenced in the format template as %distance,
// and will be formatted as a fixed-point number with 2 decimal places.
//
// stringf(), along with FormatArg and formatarg() is a wrapper around
// string_format(const char* fmt, int numargs, const FormatArg * const args[])
//
// Syntax for argument references:
// ref = '%' ( ident | int | '{' [^}]+ '}' ) ( '{' formatspec '}' )?
// int = [0-9]+
// ident = [a-zA-Z_] [a-zA-Z0-9_]*
// alpha = [a-zA-Z]
// formatspec = alpha+ ( ':'? fmtparam ( '|' fmtparam)* )
// fmtparam = ( [^}\] | '\' any )*
//
// To insert a literal % character, use %% (as in printf)
//
// References are either an integer argument index (0-based),
// or a text string, which can follow C identifier rules, or be any string
// enclosed in braces.
//
// The format specifier, if provided, consists of a style name, followed by
// a series of parameters. Style names are alphabetic only (no underscore,
// digits or puncutation). Parameters may immediately follow the style name,
// or be separated from the style name by a colon.
// Parameters are separated from each other by a pipe character.
// Backslash may be used within format parameters to escape '|' and '}',
// more generally, backslash within a format parameter causes the next
// character to be taken as a literal, regardless of what that character is
//
// Examples of references:
// stringf("Hello, %0.", "Jameson") -> "Hello, Jameson."
// stringf("Hello, %0.", formatarg("name", "Jameson")) -> "Hello, Jameson."
// stringf("Hello, %name.", formatarg("name", "Jameson")) -> "Hello, Jameson."
// stringf("That's %{mood}tastic!", formatarg("mood", "funky")) -> "That's funkytastic!"
//
// stringf("I've already wasted %count %{trip(s)} on this fooling endeavour!",
// formatarg("count", 3), formatarg("trip(s)", "trips"))
// -> "I've already wasted 3 trips on this fooling endeavour!"
//
// stringf("I've already wasted %count %{trip(s)} on this fooling endeavour!",
// formatarg("count", 1), formatarg("trip(s)", "trip"))
// -> "I've already wasted 1 trip on this fooling endeavour!"
//
// stringf("That'll be %0 credits, Mr. %1.", 50, "Jameson")
// -> "That'll be 50 credits, Mr. Jameson."
// stringf("Excellent choice, Mr. %1! That'll be %0 credits, please.", 50, "Jameson")
// -> "Excellent choice, Mr. Jameson! That'll be 50 credits, please."
//
// Currently implemented format styles are designed to mostly match printf()
// specifiers, except to follow the general syntax described above, the
// specifier itself comes first, then any flags as a parameter. Only numeric
// types currently interpret these format specifiers. So:
//
// printf("%s", "Hello") =~= stringf("%0", "Hello")
// printf("%f", 42.125) =~= stringf("%0{f}", 42.125)
// printf("%.2f", 42.125) =~= stringf("%0{f.2}", 42.125)
// printf("%+2.3f", 42.125) =~= stringf("%0{f+2.3}", 42.125)
// printf("%08d", 42) =~= stringf("%0{d08}", 42)
//

class FormatSpec {
public:
FormatSpec();
FormatSpec(const char* format);
FormatSpec(const char* format, int formatlen);

bool empty() const;

// access to components of the formatspec
bool specifierIs(const char* specifier) const;
int paramCount() const;
std::string param(int idx) const;
void paramPtr(int idx, const char*& begin, const char*& end) const;

private:
static const int MAX_PARAMS = 3;

void parseFormat(int length);

const char * const format;
// each entry in the params array specifies the index within format[]
// of the first byte in the parameter
uint16_t params[MAX_PARAMS+1];
};

std::string to_string(int32_t value, const FormatSpec& fmt);
std::string to_string(int64_t value, const FormatSpec& fmt);
std::string to_string(uint32_t value, const FormatSpec& fmt);
std::string to_string(uint64_t value, const FormatSpec& fmt);
std::string to_string(float value, const FormatSpec& fmt);
std::string to_string(double value, const FormatSpec& fmt);
std::string to_string(fixed value, const FormatSpec& fmt);
std::string to_string(const char* value, const FormatSpec& fmt);
std::string to_string(const std::string& value, const FormatSpec& fmt);

inline std::string to_string(int32_t value, const FormatSpec& fmt) {
return to_string(int64_t(value), fmt);
}

inline std::string to_string(uint32_t value, const FormatSpec& fmt) {
return to_string(uint64_t(value), fmt);
}

inline std::string to_string(float value, const FormatSpec& fmt) {
return to_string(double(value), fmt);
}

inline std::string to_string(fixed value, const FormatSpec& fmt) {
return to_string(value.ToDouble(), fmt);
}

template <typename T>
inline std::string to_string(const T& value) {
return to_string(value, FormatSpec());
}

class FormatArg {
public:
explicit FormatArg(const char* name_ = 0, const char* defaultformat_ = 0):
name(name_), defaultformat(defaultformat_) {}

char const * const name;
char const * const defaultformat;

virtual std::string format(const FormatSpec& spec) const = 0;
};

template <typename T>
class FormatArgT : public FormatArg {
public:
FormatArgT(const char* name_, const T& value_, const char* defaultformat_):
FormatArg(name_, defaultformat_), value(value_) {}

virtual std::string format(const FormatSpec& spec) const {
return to_string(value, spec);
}

private:
const T value;
};

// ---------------------------------------------------------------------------

template <typename T> struct FormatArgWrapper;

template <typename T> struct FormatArgWrapper {
typedef FormatArgT<T> type;
static type wrap(const T& arg, const char* name = 0, const char* defaultformat = 0)
{ return FormatArgT<T>(name, arg, defaultformat); }
};
template <int N> struct FormatArgWrapper<char[N]> {
typedef FormatArgT<const char*> type;
static type wrap(const char (&arg)[N], const char* name = 0, const char* defaultformat = 0)
{ return FormatArgT<const char*>(name, arg, defaultformat); }
};
template <> struct FormatArgWrapper<char[]> {
typedef FormatArgT<const char*> type;
static type wrap(const char *arg, const char* name = 0, const char* defaultformat = 0)
{ return FormatArgT<const char*>(name, arg, defaultformat); }
};
template <> struct FormatArgWrapper<FormatArg> {
typedef FormatArg type;
static const type& wrap(const FormatArg& arg) { return arg; }
};
template <typename T> struct FormatArgWrapper< FormatArgT<T> > {
typedef FormatArgT<T> type;
static const type& wrap(const FormatArgT<T>& arg) { return arg; }
};

// ---------------------------------------------------------------------------

// this version is safer (doesn't rely on the value out-living the FormatArgT object)
// but performs a string copy
/*
FormatArgT<std::string> formatarg(const char* name, const char* value) {
return FormatArgT<std::string>(name, std::string(value));
}
*/

template <typename T>
inline typename FormatArgWrapper<T>::type
formatarg(const char* name, const T& value, const char* defaultformat = 0) {
return FormatArgWrapper<T>::wrap(value, name, defaultformat);
}

// underlying formatting function

std::string string_format(const char* fmt, int numargs, FormatArg const * const args[]);

// ---------------------------------------------------------------------------

// ---- stringf(format, args...) for 0 to 7 arguments ----

inline std::string stringf(const char* fmt) {
return string_format(fmt, 0, 0);
}

template <typename T0>
inline std::string stringf(const char* fmt, const T0& p0) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
FormatArg const * const args[] = { &arg0 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
FormatArg const * const args[] = { &arg0, &arg1 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1, typename T2>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1, const T2& p2) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
const typename FormatArgWrapper<T2>::type& arg2 = FormatArgWrapper<T2>::wrap(p2);
FormatArg const * const args[] = { &arg0, &arg1, &arg2 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1, typename T2, typename T3>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1, const T2& p2, const T3& p3) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
const typename FormatArgWrapper<T2>::type& arg2 = FormatArgWrapper<T2>::wrap(p2);
const typename FormatArgWrapper<T3>::type& arg3 = FormatArgWrapper<T3>::wrap(p3);
FormatArg const * const args[] = { &arg0, &arg1, &arg2, &arg3 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1, typename T2, typename T3, typename T4>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1, const T2& p2, const T3& p3, const T4& p4) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
const typename FormatArgWrapper<T2>::type& arg2 = FormatArgWrapper<T2>::wrap(p2);
const typename FormatArgWrapper<T3>::type& arg3 = FormatArgWrapper<T3>::wrap(p3);
const typename FormatArgWrapper<T4>::type& arg4 = FormatArgWrapper<T4>::wrap(p4);
FormatArg const * const args[] = { &arg0, &arg1, &arg2, &arg3, &arg4 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1, typename T2, typename T3, typename T4, typename T5>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1, const T2& p2, const T3& p3, const T4& p4, const T5& p5) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
const typename FormatArgWrapper<T2>::type& arg2 = FormatArgWrapper<T2>::wrap(p2);
const typename FormatArgWrapper<T3>::type& arg3 = FormatArgWrapper<T3>::wrap(p3);
const typename FormatArgWrapper<T4>::type& arg4 = FormatArgWrapper<T4>::wrap(p4);
const typename FormatArgWrapper<T5>::type& arg5 = FormatArgWrapper<T5>::wrap(p5);
FormatArg const * const args[] = { &arg0, &arg1, &arg2, &arg3, &arg4, &arg5 };
return string_format(fmt, COUNTOF(args), args);
}

template <typename T0, typename T1, typename T2, typename T3, typename T4, typename T5, typename T6>
inline std::string stringf(const char* fmt, const T0& p0, const T1& p1, const T2& p2, const T3& p3, const T4& p4, const T5& p5, const T6& p6) {
const typename FormatArgWrapper<T0>::type& arg0 = FormatArgWrapper<T0>::wrap(p0);
const typename FormatArgWrapper<T1>::type& arg1 = FormatArgWrapper<T1>::wrap(p1);
const typename FormatArgWrapper<T2>::type& arg2 = FormatArgWrapper<T2>::wrap(p2);
const typename FormatArgWrapper<T3>::type& arg3 = FormatArgWrapper<T3>::wrap(p3);
const typename FormatArgWrapper<T4>::type& arg4 = FormatArgWrapper<T4>::wrap(p4);
const typename FormatArgWrapper<T5>::type& arg5 = FormatArgWrapper<T5>::wrap(p5);
const typename FormatArgWrapper<T6>::type& arg6 = FormatArgWrapper<T6>::wrap(p6);
FormatArg const * const args[] = { &arg0, &arg1, &arg2, &arg3, &arg4, &arg5, &arg6 };
return string_format(fmt, COUNTOF(args), args);
}

#endif
Something went wrong with that request. Please try again.