Typedef not a member of namespace - c++

Question

So, I'm attempting to fork some open source code and upon compilation I am greeted with these errors:
C2039 'TransactionId': is not a member of 'CryptoNote'
C2061 syntax error: identifier 'TransactionId'
I'm relatively inexperienced with C++ usually confining myself to the realms of C#, however, I can clearly see that TransactionId is a typedef declared in a different file like so:
namespace CryptoNote {
typedef size_t TransactionId;
typedef size_t TransferId;
//more code
And the line throwing the error is:
void sendTransactionCompleted(CryptoNote::TransactionId _id, bool _error, const QString& _error_text);
To my inexperienced eyes, that looks as though TransactionID is definitly a member of Cryptonote is it not?
Any ideas what's going on?
The repo is here: https://github.com/hughesjs/Incendium_GUI
And the necessary submodule is here: https://github.com/hughesjs/Incendium_Crypt

Answer 1

Those typedefs are defined in Incendium_Crypt/include/IWalletLegacy.h.
void sendTransactionCompleted(CryptoNote::TransactionId _id, bool _error, const QString& _error_text);`
is defined in Incendium_GUI/src/gui/SendFrame.h, which includes IWallet.h. However, IWallet.h does not in turn include IWalletLegacy.h. Hence, those typedefs are unknown to SendFrame.h.

Answer 2

It's difficult to say without seeing all the code but a few things come to mind:
Firstly is this the first error you get. Compilation errors with C++ tend to result in a bunch of secondary errors. For example the following results in a similar error to what you see but fails to compile because size_t has not been defined:
namespace CryptoNote {
typedef size_t TransactionId;
typedef size_t TransferId;
}
int main(void)
{
CryptoNote::TransactionId id;
return 0;
}
$ g++ -std=c++11 namespace.cxx -o namespace
namespace.cxx:4:9: error: ‘size_t’ does not name a type
typedef size_t TransactionId;
^~~~~~
namespace.cxx:5:9: error: ‘size_t’ does not name a type
typedef size_t TransferId;
^~~~~~
namespace.cxx: In function ‘int main()’:
namespace.cxx:11:17: error: ‘TransactionId’ is not a member of ‘CryptoNote’
CryptoNote::TransactionId id;
^~~~~~~~~~~~~
See http://www.cplusplus.com/reference/cstring/size_t/ for a list of headers that define size_t.
Is CryptoNote nested inside another namespace?
Is there another CryptoNote defined in the namespace your function is declared in?
Are these in the same header file? If not, is the header file where the namespace is defined included in the header file containing the function declaration?