From 32f18cd992b5b6988a3b37eaa533f8215d83fe2e Mon Sep 17 00:00:00 2001 From: Jaskamal Kainth Date: Thu, 28 Jan 2016 10:38:51 +0530 Subject: Added Tuple --- c++.html.markdown | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index 44cad665..b8ab656c 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -955,6 +955,54 @@ v.push_back(Foo()); // New value is copied into the first Foo we inserted // explanation of why this works. v.swap(vector()); + +/////////////////////////////////////// +// Tuples (C++11 and above) +/////////////////////////////////////// + +#include + +// Conceptually, Tuples are similar to old data structures (C-like structs) but instead of having named data members , +// its elements are accessed by their order in the tuple. + +// We start with constructing a tuple. +// +// Packing values into tuple +auto first = make_tuple ( 10 , 'A' ) ; +const int maxN = 1e9; +int maxL = 15; +auto second = make_tuple ( maxN , maxL ) ; + +// printing elements of 'first' tuple +cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A + +// printing elements of 'second' tuple +cout << get<0>(second)<< " " << get<1>(second) << "\n"; // prints: 1000000000 15 + + +// Unpacking tuple into variables + +int first_int; +char first_char; +tie (first_int , first_char ) = first; +cout << first_int << " " << first_char << "\n"; // prints : 10 A + +// We can also create tuple like this. + +tuple third ( 11 ,'A' , 3.14141); +// tuple_size returns number of elements in a tuple (as a constexpr) + +cout << tuple_size< decltype(third)>::value << "\n"; // prints: 3 + +// tuple_cat concatenates the elements of all the tuples in the same order. + +auto concatenated_tuple = tuple_cat( first, second ,third); +// concatenated_tuple becomes = (10 , 'A' , 1e9 , 15 , 11 , 'A' , 3.14141 ) + +cout << get<0>(concatenated_tuple) << "\n"; // prints: 10 +cout << get<3>(concatenated_tuple) << "\n"; // prints: 15 +cout << get<5>(concatenated_tuple) << "\n"; // prints: 'A' + ``` Further Reading: -- cgit v1.2.3 From c805148618f5b2679d6581ff41885abc7140fd4d Mon Sep 17 00:00:00 2001 From: Jaskamal Kainth Date: Thu, 28 Jan 2016 15:26:35 +0530 Subject: [C++/en] Tuples in C++ --- c++.html.markdown | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index b8ab656c..594cf15f 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -966,25 +966,24 @@ v.swap(vector()); // its elements are accessed by their order in the tuple. // We start with constructing a tuple. -// // Packing values into tuple -auto first = make_tuple ( 10 , 'A' ) ; +auto first = make_tuple( 10 , 'A' ) ; const int maxN = 1e9; -int maxL = 15; -auto second = make_tuple ( maxN , maxL ) ; +const int maxL = 15; +auto second = make_tuple( maxN , maxL ) ; // printing elements of 'first' tuple cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A // printing elements of 'second' tuple -cout << get<0>(second)<< " " << get<1>(second) << "\n"; // prints: 1000000000 15 +cout << get<0>(second) << " " << get<1>(second) << "\n"; // prints: 1000000000 15 // Unpacking tuple into variables int first_int; char first_char; -tie (first_int , first_char ) = first; +tie(first_int , first_char ) = first; cout << first_int << " " << first_char << "\n"; // prints : 10 A // We can also create tuple like this. @@ -992,7 +991,7 @@ cout << first_int << " " << first_char << "\n"; // prints : 10 A tuple third ( 11 ,'A' , 3.14141); // tuple_size returns number of elements in a tuple (as a constexpr) -cout << tuple_size< decltype(third)>::value << "\n"; // prints: 3 +cout << tuple_size < decltype(third) >::value << "\n"; // prints: 3 // tuple_cat concatenates the elements of all the tuples in the same order. -- cgit v1.2.3 From 4a1a6857ce30f19f8c04dcca4571bb27f7dc36d0 Mon Sep 17 00:00:00 2001 From: Jaskamal Kainth Date: Thu, 28 Jan 2016 17:15:44 +0530 Subject: [C++/en] Tuple , updated --- c++.html.markdown | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index 594cf15f..ea6ef034 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -967,10 +967,10 @@ v.swap(vector()); // We start with constructing a tuple. // Packing values into tuple -auto first = make_tuple( 10 , 'A' ) ; +auto first = make_tuple(10,'A') ; const int maxN = 1e9; const int maxL = 15; -auto second = make_tuple( maxN , maxL ) ; +auto second = make_tuple(maxN,maxL) ; // printing elements of 'first' tuple cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A @@ -983,12 +983,12 @@ cout << get<0>(second) << " " << get<1>(second) << "\n"; // prints: 1000000000 1 int first_int; char first_char; -tie(first_int , first_char ) = first; +tie(first_int,first_char) = first; cout << first_int << " " << first_char << "\n"; // prints : 10 A // We can also create tuple like this. -tuple third ( 11 ,'A' , 3.14141); +tuple third (11,'A',3.14141); // tuple_size returns number of elements in a tuple (as a constexpr) cout << tuple_size < decltype(third) >::value << "\n"; // prints: 3 @@ -996,7 +996,7 @@ cout << tuple_size < decltype(third) >::value << "\n"; // prints: 3 // tuple_cat concatenates the elements of all the tuples in the same order. auto concatenated_tuple = tuple_cat( first, second ,third); -// concatenated_tuple becomes = (10 , 'A' , 1e9 , 15 , 11 , 'A' , 3.14141 ) +// concatenated_tuple becomes = (10,'A',1e9,15,11,'A',3.14141) cout << get<0>(concatenated_tuple) << "\n"; // prints: 10 cout << get<3>(concatenated_tuple) << "\n"; // prints: 15 -- cgit v1.2.3 From fa2b171008061bc82cf9b35e0470eebeaecb4a26 Mon Sep 17 00:00:00 2001 From: Jaskamal Kainth Date: Thu, 28 Jan 2016 18:22:11 +0530 Subject: [C++/en] Tuple , Updated --- c++.html.markdown | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index ea6ef034..1065b9e8 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -967,10 +967,10 @@ v.swap(vector()); // We start with constructing a tuple. // Packing values into tuple -auto first = make_tuple(10,'A') ; +auto first = make_tuple(10,'A'); const int maxN = 1e9; const int maxL = 15; -auto second = make_tuple(maxN,maxL) ; +auto second = make_tuple(maxN,maxL); // printing elements of 'first' tuple cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A @@ -978,7 +978,6 @@ cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A // printing elements of 'second' tuple cout << get<0>(second) << " " << get<1>(second) << "\n"; // prints: 1000000000 15 - // Unpacking tuple into variables int first_int; -- cgit v1.2.3 From e1016455d5e4472e7a533c8cdd6df8ae4f2e7854 Mon Sep 17 00:00:00 2001 From: ven Date: Thu, 28 Jan 2016 14:04:41 +0100 Subject: #2119 fixups --- c++.html.markdown | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index 1065b9e8..82662b15 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -967,10 +967,10 @@ v.swap(vector()); // We start with constructing a tuple. // Packing values into tuple -auto first = make_tuple(10,'A'); +auto first = make_tuple(10, 'A'); const int maxN = 1e9; const int maxL = 15; -auto second = make_tuple(maxN,maxL); +auto second = make_tuple(maxN, maxL); // printing elements of 'first' tuple cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A @@ -982,20 +982,20 @@ cout << get<0>(second) << " " << get<1>(second) << "\n"; // prints: 1000000000 1 int first_int; char first_char; -tie(first_int,first_char) = first; +tie(first_int, first_char) = first; cout << first_int << " " << first_char << "\n"; // prints : 10 A // We can also create tuple like this. -tuple third (11,'A',3.14141); +tuple third(11, 'A', 3.14141); // tuple_size returns number of elements in a tuple (as a constexpr) -cout << tuple_size < decltype(third) >::value << "\n"; // prints: 3 +cout << tuple_size::value << "\n"; // prints: 3 // tuple_cat concatenates the elements of all the tuples in the same order. -auto concatenated_tuple = tuple_cat( first, second ,third); -// concatenated_tuple becomes = (10,'A',1e9,15,11,'A',3.14141) +auto concatenated_tuple = tuple_cat(first, second, third); +// concatenated_tuple becomes = (10, 'A', 1e9, 15, 11, 'A' ,3.14141) cout << get<0>(concatenated_tuple) << "\n"; // prints: 10 cout << get<3>(concatenated_tuple) << "\n"; // prints: 15 -- cgit v1.2.3 From 1bb2535efda67de687d4eb94a0f964f9c06dcd4a Mon Sep 17 00:00:00 2001 From: AndrejPetelin Date: Sun, 31 Jan 2016 16:08:28 +0100 Subject: Update c++.html.markdown v.empty() queries if v is empty while v.clear() actually clears it (or rather sets size to 0). --- c++.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'c++.html.markdown') diff --git a/c++.html.markdown b/c++.html.markdown index 82662b15..a59b4db8 100644 --- a/c++.html.markdown +++ b/c++.html.markdown @@ -948,7 +948,7 @@ for (int i = 0; i < 10; ++i) // Following line sets size of v to 0, but destructors don't get called // and resources aren't released! -v.empty(); +v.clear(); v.push_back(Foo()); // New value is copied into the first Foo we inserted // Truly destroys all values in v. See section about temporary objects for -- cgit v1.2.3