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Extend internal API docs, part 2

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Picking up from #8111.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
This commit is contained in:
John Ericson 2023-03-26 21:12:25 -04:00
parent 8ae9d66940
commit abd5e7dec0
32 changed files with 640 additions and 359 deletions
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46
src/libutil/types.hh
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@ -17,7 +17,9 @@ typedef std::set<std::string> StringSet;
typedef std::map<std::string, std::string> StringMap;
typedef std::map<std::string, std::string> StringPairs;
/* Paths are just strings. */
/**
* Paths are just strings.
*/
typedef std::string Path;
typedef std::string_view PathView;
typedef std::list<Path> Paths;
@ -25,15 +27,19 @@ typedef std::set<Path> PathSet;
typedef std::vector<std::pair<std::string, std::string>> Headers;
/* Helper class to run code at startup. */
/**
* Helper class to run code at startup.
*/
template<typename T>
struct OnStartup
{
OnStartup(T && t) { t(); }
};
/* Wrap bools to prevent string literals (i.e. 'char *') from being
cast to a bool in Attr. */
/**
* Wrap bools to prevent string literals (i.e. 'char *') from being
* cast to a bool in Attr.
*/
template<typename T>
struct Explicit {
T t;
@ -45,21 +51,25 @@ struct Explicit {
};
/* This wants to be a little bit like rust's Cow type.
Some parts of the evaluator benefit greatly from being able to reuse
existing allocations for strings, but have to be able to also use
newly allocated storage for values.
We do not define implicit conversions, even with ref qualifiers,
since those can easily become ambiguous to the reader and can degrade
into copying behaviour we want to avoid. */
/**
* This wants to be a little bit like rust's Cow type.
* Some parts of the evaluator benefit greatly from being able to reuse
* existing allocations for strings, but have to be able to also use
* newly allocated storage for values.
*
* We do not define implicit conversions, even with ref qualifiers,
* since those can easily become ambiguous to the reader and can degrade
* into copying behaviour we want to avoid.
*/
class BackedStringView {
private:
std::variant<std::string, std::string_view> data;
/* Needed to introduce a temporary since operator-> must return
a pointer. Without this we'd need to store the view object
even when we already own a string. */
/**
* Needed to introduce a temporary since operator-> must return
* a pointer. Without this we'd need to store the view object
* even when we already own a string.
*/
class Ptr {
private:
std::string_view view;
@ -77,8 +87,10 @@ public:
BackedStringView(const BackedStringView &) = delete;
BackedStringView & operator=(const BackedStringView &) = delete;
/* We only want move operations defined since the sole purpose of
this type is to avoid copies. */
/**
* We only want move operations defined since the sole purpose of
* this type is to avoid copies.
*/
BackedStringView(BackedStringView && other) = default;
BackedStringView & operator=(BackedStringView && other) = default;