95a6273
Strange to convert zero value totrue.

For conversion rules between bool and int types in the C++ language,

https://timsong-cpp.github.io/cppwp/n4659/conv.prom#6

A prvalue of typebool can be converted to a prvalue of typeint, withfalse becoming zero andtrue becoming one.

https://timsong-cpp.github.io/cppwp/n4659/conv.bool#1

A prvalue of arithmetic, unscoped enumeration, pointer, or pointer to member type can be converted to a prvalue of typebool. A zero value, null pointer value, or null member pointer value is converted tofalse; any other value is converted totrue. Fordirect-initialization, a prvalue of typestd​::​nullptr_­t can be converted to a prvalue of typebool; the resulting value isfalse.

it is preferred to make conversion function explicit unless any reason not to do so.

This is the place where we need implicit conversion. no one wants to writeif ((bool)x) { ... } anyway.

it is preferred to make conversion function explicit unless any reason not to do so.

This is the place where we need implicit conversion. no one wants to writeif ((bool)x) { ... } anyway.

You can writeif (x) { ... } even if the conversion operator to bool is marked as explicit.

cf.https://en.cppreference.com/w/cpp/language/implicit_conversion#Contextual_conversions

This repositorydoes not accept requests for new features.

For now, we are not planning to add new features

In this case, I don't think it's necessary because you can add a custom bool cast as shown below:

#include<atcoder/modint>#include<bits/stdc++.h>structmint :publicmodint998244353 {using static_modint::static_modint;mint(modint998244353  m) : modint998244353 (m) {}operatorbool()const {returnval() !=0; }};intmain() {    mintm(123);if (m) {puts("not zero");    }else {puts("zero");    }}