ladybird/AK/StringView.h
Andreas Kling 0e75aba7c3 StringView: Rename characters() to characters_without_null_termination().
This should make you think twice before trying to use the const char* from
a StringView as if it's a null-terminated string.
2019-07-08 15:38:44 +02:00

93 lines
2.8 KiB
C++

#pragma once
#include <AK/Vector.h>
namespace AK {
class ByteBuffer;
class String;
class StringImpl;
class StringView {
public:
StringView() {}
StringView(const char* characters, int length)
: m_characters(characters)
, m_length(length)
{
}
StringView(const unsigned char* characters, int length)
: m_characters((const char*)characters)
, m_length(length)
{
}
StringView(const char* cstring)
: m_characters(cstring)
{
if (cstring) {
while (*(cstring++))
++m_length;
}
}
StringView(const ByteBuffer&);
StringView(const String&);
bool is_null() const { return !m_characters; }
bool is_empty() const { return m_length == 0; }
const char* characters_without_null_termination() const { return m_characters; }
int length() const { return m_length; }
char operator[](int index) const { return m_characters[index]; }
StringView substring_view(int start, int length) const;
Vector<StringView> split_view(char) const;
unsigned to_uint(bool& ok) const;
// Create a new substring view of this string view, starting either at the beginning of
// the given substring view, or after its end, and continuing until the end of this string
// view (that is, for the remaining part of its length). For example,
//
// StringView str { "foobar" };
// StringView substr = str.substring_view(1, 2); // "oo"
// StringView substr_from = str.substring_view_starting_from_substring(subst); // "oobar"
// StringView substr_after = str.substring_view_starting_after_substring(subst); // "bar"
//
// Note that this only works if the string view passed as an argument is indeed a substring
// view of this string view, such as one created by substring_view() and split_view(). It
// does not work for arbitrary strings; for example declaring substr in the example above as
//
// StringView substr { "oo" };
//
// would not work.
StringView substring_view_starting_from_substring(const StringView& substring) const;
StringView substring_view_starting_after_substring(const StringView& substring) const;
bool operator==(const char* cstring) const
{
if (is_null())
return !cstring;
if (!cstring)
return false;
int other_length = strlen(cstring);
if (m_length != other_length)
return false;
return !memcmp(m_characters, cstring, m_length);
}
bool operator!=(const char* cstring) const
{
return !(*this == cstring);
}
bool operator==(const String&) const;
private:
friend class String;
const StringImpl* m_impl { nullptr };
const char* m_characters { nullptr };
int m_length { 0 };
};
}
using AK::StringView;