Debug

In the process of developing smart contracts, debugging is a very important part. Currently, the main way to debug smart contracts is to print the relevant logs to the witness console using the interface provided by the GXChain blockchain.Therefore, it is necessary to build a private chain or start a synchronous test network node locally.

before debugging, you need to do two things:

1. Modify the local config.ini file :

[logger.default]
level=debug
appenders=stderr,FILE

2. Start the witness_node with the parameters --contracts-console

The print debugging method implements overloaded implementation of multiple parameter types. Support for strings, int types, floating point numbers, hexadecimal, etc.

print

prints

//Print string： const char*
prints("hello");
Output: hello

prints_l

//Print the first few characters of a string
prints_l("hello",3);
Output: hel

printi

//Print signed number with int64_t type
printi(-1);
Output: -1

printui

//Print unsigned number with parameter uint64_t
printui(-1);
Output: 18446744073709551615

printdf

//Print floating point number, the parameter is double
printdf(3.14159);
Output: 3.141590000000000e+00

printn

//Print base32 encrypted results
printn(N(hello));
Output: hello

printhex

//Print hexadecimal
std::string str="hello";
checksum256 sum;
sha256(str.c_str(),str.length(),&sum);
printhex(sum.hash,32);
Output：2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824