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POProblem understanding explicit constructor in C++
 

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  1. POProblem understanding explicit constructor in C++
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    <p>After reading this thread <a href="https://stackoverflow.com/questions/121162/what-does-the-explicit-keyword-in-c-mean">What does the explicit keyword mean in C++?</a></p> <p>I made up this program</p> <pre><code>class MyClass { public: explicit MyClass(int a) { cout&lt;&lt;"Int was called"&lt;&lt;endl; val = a; } MyClass(char *a) { cout&lt;&lt;"Char was called"&lt;&lt;endl; val = atoi(a); } MyClass(const MyClass&amp; copy) { cout&lt;&lt;"Copy Const was called"&lt;&lt;endl; this-&gt;val = copy.val; } inline const int getval() const { return val; } private: int val ; }; </code></pre> <p>main code</p> <pre><code>int main() { int x=4; char y='4'; char *z = &amp;y; MyClass a(x); MyClass b(z); MyClass c(a); MyClass d('4'); cout&lt;&lt;a.getval()&lt;&lt;endl; cout&lt;&lt;b.getval()&lt;&lt;endl; cout&lt;&lt;c.getval()&lt;&lt;endl; cout&lt;&lt;d.getval()&lt;&lt;endl; return 0; } </code></pre> <p>The output was:</p> <pre><code>Int was called Char was called Copy Const was called Int was called 4 4 4 52 </code></pre> <p>Now, as per thread above, it should throw error after the constructor call on object d but it didn't. </p> <p>g++ version info</p> <pre><code>Using built-in specs. Target: i486-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.4.3-4ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared --enable-multiarch --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4 --program-suffix=-4.4 --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-plugin --enable-objc-gc --enable-targets=all --disable-werror --with-arch-32=i486 --with-tune=generic --enable-checking=release --build=i486-linux-gnu --host=i486-linux-gnu --target=i486-linux-gnu Thread model: posix gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5) </code></pre> <p>I am not sure if i have done something wrong in the above code. Please help</p>
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    1. COWhy did you expect an error in while constructing `d`?
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      1. POProblem understanding explicit constructor in C++
      1. USDavid Rodríguez - dribeas
 

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