What is the difference between isdigit() and isnumber()?

isnumber() may be an Apple-specific C++ method (I don’t have a Mac on hand to check). You can see it in the Apple dev guide:

The isnumber() function behaves similarly to isdigit(), but may recognize additional characters, depending on the current locale setting.

Besides, isnumber() is not declared on Linux: I use g++ 6.1.1 on Linux 4.7.2 and get the error:

g++ a.cpp
a.cpp: In function 'int main(int, char**)':
a.cpp:20:17: error: 'isnumber' was not declared in this scope
   if (isnumber(i)) {
                 ^

I also use clang3.8.1 to test:

clang++ a.cpp --std=c++11
a.cpp:20:7: error: use of undeclared identifier 'isnumber'
                if (isnumber(i)) {
                    ^

Related Posts:

  1. Why the switch statement cannot be applied on strings?
  2. How to convert string to char array in C++?
  3. How can I convert a std::string to int?
  4. Easiest way to convert int to string in C++
  5. std::string to char*
  6. How to convert string to char array in C++?
  7. C++ — expected primary-expression before ‘ ‘
  8. C++ string to double conversion
  9. Conversion from string to char – c++
  10. What is `CString`?
  11. How do I include the string header?
  12. Differences between C++ string == and compare()?
  13. How to convert a char array to a string?
  14. How do I convert a double into a string in C++?
  15. Split a string using C++11
  16. How do I iterate over the words of a string?
  17. How to convert an instance of std::string to lower case
  18. Check if a string contains a string in C++
  19. How do I iterate over the words of a string?
  20. Returning an empty string : efficient way in c++
  21. Replace part of a string with another string
  22. What is use of c_str function In c++
  23. How to reverse an std::string? [duplicate]
  24. C++ Parsing input string to variables
  25. std::string to char*
  26. How to convert a std::string to const char* or char*
  27. How do I tokenize a string in C++?
  28. Why am I getting string does not name a type Error?
  29. C++ deprecated conversion from string constant to ‘char*’
  30. identifier “string” undefined?
  31. Press Enter to Continue
  32. Converting a vector to string
  33. Parsing a comma-delimited std::string
  34. How can I convert const char* to string and then back to char*?
  35. std::string formatting like sprintf
  36. Sorting Characters Of A C++ String
  37. basic_string::_M_construct null not valid after constructing subvector of strings
  38. How to copy a string of std::string type in C++?
  39. How to return a string from a C++ function?
  40. std::out_of_range error?
  41. Convert char* to string C++
  42. printf with std::string?
  43. Convert a String In C++ To Upper Case
  44. Right way to split an std::string into a vector
  45. Read whole ASCII file into C++ std::string
  46. C++: std does not have member “string”
  47. Right way to split an std::string into a vector
  48. string subscript out of range error
  49. C++ String Variable Declaration
  50. Returning an empty string : efficient way in c++
  51. Split a string into an array in C++
  52. splitting a string into an array in C++ without using vector
  53. Remove spaces from std::string in C++
  54. Remove spaces from std::string in C++
  55. c++ convert string to hex
  56. How can I iterate through a string and also know the index (current position)?
  57. c++ parse int from string [duplicate]
  58. Hash function for a string
  59. C++ strings and pointers
  60. How to Convert a C++ String to Uppercase
  61. std::wstring VS std::string
  62. C++ Simple hangman game
  63. std::cin input with spaces?
  64. Remove First and Last Character C++
  65. C++ Remove punctuation from String
  66. C++ string to enum
  67. C++ Convert string (or char*) to wstring (or wchar_t*)
  68. C++ – Assigning null to a std::string
  69. How to alphabetically sort strings?
  70. Hash function for a string
  71. Reading string by char till end of line C/C++
  72. Dynamically allocated string array, then change it’s value?
  73. Fastest way to Convert String to Binary?
  74. Why I cannot cout a string?
  75. How to print a string in C++
  76. std::string length() and size() member functions
  77. How to convert QString to int?
  78. Which is faster C++ String length() or size()?
  79. How do I create a random alpha-numeric string in C++?
  80. Is string::compare reliable to determine alphabetical order?
  81. Trying to use int in getline
  82. error: switch quantity not an integer
  83. Reading a string from file c++
  84. How to change string into QString?
  85. Remove last character from C++ string
  86. Converting String to Cstring in C++
  87. c++ sizeof( string )
  88. How to do std::string indexof in C++ that returns index of matching string?
  89. variable or field declared void
  90. Function stoi not declared
  91. Understanding error “terminate called after throwing an instance of ‘std::length_error’ what(): basic_string::_S_create Aborted (core dumped)”
  92. convert string to size_t
  93. ‘setprecision’ is not a member of ‘std’
  94. enum to string in modern C++11 / C++14 / C++17 and future C++20
  95. Converting bool to text in C++
  96. Why are there two different getline() functions (if indeed there are)?
  97. Why does my program give “NULL used in arithmetic”
  98. How to find and replace string?
  99. Declaration is incompatible with type
  100. I’m getting the error “stoi is not a member of std” in myprogramminglab [duplicate]

Leave a Comment

techhipbettruvabetnorabahisbahis forumutaraftarium24edusedueduedueduedusedusedusedusedus