Value: extract Value::StringWithContext

This commit is contained in:
Robert Hensing 2023-11-12 03:02:02 +01:00
parent 7ba4e073e8
commit 2eb59c34b5

View file

@ -158,37 +158,39 @@ public:
inline bool isPrimOp() const { return internalType == tPrimOp; }; inline bool isPrimOp() const { return internalType == tPrimOp; };
inline bool isPrimOpApp() const { return internalType == tPrimOpApp; }; inline bool isPrimOpApp() const { return internalType == tPrimOpApp; };
/**
* Strings in the evaluator carry a so-called `context` which
* is a list of strings representing store paths. This is to
* allow users to write things like
*
* "--with-freetype2-library=" + freetype + "/lib"
*
* where `freetype` is a derivation (or a source to be copied
* to the store). If we just concatenated the strings without
* keeping track of the referenced store paths, then if the
* string is used as a derivation attribute, the derivation
* will not have the correct dependencies in its inputDrvs and
* inputSrcs.
* The semantics of the context is as follows: when a string
* with context C is used as a derivation attribute, then the
* derivations in C will be added to the inputDrvs of the
* derivation, and the other store paths in C will be added to
* the inputSrcs of the derivations.
* For canonicity, the store paths should be in sorted order.
*/
struct StringWithContext {
const char * c_str;
const char * * context; // must be in sorted order
};
union union
{ {
NixInt integer; NixInt integer;
bool boolean; bool boolean;
/** StringWithContext string;
* Strings in the evaluator carry a so-called `context` which
* is a list of strings representing store paths. This is to
* allow users to write things like
* "--with-freetype2-library=" + freetype + "/lib"
* where `freetype` is a derivation (or a source to be copied
* to the store). If we just concatenated the strings without
* keeping track of the referenced store paths, then if the
* string is used as a derivation attribute, the derivation
* will not have the correct dependencies in its inputDrvs and
* inputSrcs.
* The semantics of the context is as follows: when a string
* with context C is used as a derivation attribute, then the
* derivations in C will be added to the inputDrvs of the
* derivation, and the other store paths in C will be added to
* the inputSrcs of the derivations.
* For canonicity, the store paths should be in sorted order.
*/
struct {
const char * c_str;
const char * * context; // must be in sorted order
} string;
struct { struct {
InputAccessor * accessor; InputAccessor * accessor;