Reference

C++ Quick Fixes

If you use the Clang code model to parse the C++ files, you get Clang fix-it hints in the Edit mode. Use the standard ways of activating quick fixes, or select the fixes that are applicable on a line in the context menu in the left margin of the code editor.

Apply the following types of quick fixes to C++ code:

  • Change binary operands
  • Simplify if and while conditions (for example, move declarations out of if conditions)
  • Modify strings (for example, set the encoding for a string to Latin-1, mark strings translatable, and convert symbol names to camel case)
  • Create variable declarations
  • Create function declarations and definitions

The following table summarizes the quick fixes for C++ code. The fix is available when the cursor is in the position described in the Activation column.

Quick FixDescriptionActivation
Add Curly BracesAdds curly braces to an if statement that does not have a compound statement. For example, rewrites
if (a)
    b;

as

if (a) {
    b;
}
if
Move Declaration out of ConditionMoves a declaration out of an if or while condition to simplify the condition. For example, rewrites
if (Type name = foo()) {}

as

Type name = foo;
if (name) {}
Name of the introduced variable
Rewrite Condition Using ||Rewrites the expression according to De Morgan's laws. For example, rewrites:
!a && !b

as

!(a || b)
&&
Rewrite Using operatorRewrites an expression negating it and using the inverse operator. For example, rewrites:
  • a op b

    as

    !(a invop b)
  • (a op b)

    as

    !(a invop b)
  • !(a op b)

    as

    (a invob b)
<=, <, >, >=, == or !=
Split DeclarationSplits a simple declaration into several declarations. For example, rewrites:
int *a, b;

as

int *a;
int b;
Type name or variable name
Split if StatementSplits an if statement into several statements. For example, rewrites:
if (something && something_else) {
}

as

if (something) {
   if (something_else) {
   }
}

and

if (something || something_else)
    x;

with

if (something)
    x;
else if (something_else)
    x;
&& or ||
Swap OperandsRewrites an expression in the inverse order using the inverse operator. For example, rewrites:
a op b

as

b flipop a
<=, <, >, >=, ==, !=, && or ||
Convert to DecimalConverts an integer literal to decimal representationNumeric literal
Convert to HexadecimalConverts an integer literal to hexadecimal representationNumeric literal
Convert to OctalConverts an integer literal to octal representationNumeric literal
Convert to Objective-C String LiteralConverts a string literal to an Objective-C string literal if the file type is Objective-C(++). For example, rewrites the following strings
"abcd"
QLatin1String("abcd")
QLatin1Literal("abcd")

as

@"abcd"
String literal
Enclose in QLatin1Char()Sets the encoding for a character to Latin-1, unless the character is already enclosed in QLatin1Char, QT_TRANSLATE_NOOP, tr, trUtf8, QLatin1Literal, or QLatin1String. For example, rewrites
'a'

as

QLatin1Char('a')
String literal
Enclose in QLatin1String()Sets the encoding for a string to Latin-1, unless the string is already enclosed in QLatin1Char, QT_TRANSLATE_NOOP, tr, trUtf8, QLatin1Literal, or QLatin1String. For example, rewrites
"abcd"

as

QLatin1String("abcd")
String literal
Enclose in QByteArrayLiteral()Converts a string to a byte array. For example, rewrites
"abcd"

as

QByteArrayLiteral("abcd")
String literal
Mark as TranslatableMarks a string translatable. For example, rewrites "abcd" with one of the following options, depending on which of them is available:
tr("abcd")
QCoreApplication::translate("CONTEXT", "abcd")
QT_TRANSLATE_NOOP("GLOBAL", "abcd")
String literal
Add Definition in ...Inserts a definition stub for a function declaration either in the header file (inside or outside the class) or in the implementation file. For free functions, inserts the definition after the declaration of the function or in the implementation file. Qualified names are minimized when possible, instead of always being fully expanded.

For example, rewrites

Class Foo {
    void bar();
};

as (inside class)

Class Foo {
    void bar() {

    }
};

as (outside class)

Class Foo {
    void bar();
};

void Foo::bar()
{

}

as (in implementation file)

// Header file
Class Foo {
    void bar();
};

// Implementation file
void Foo::bar()
{

}
Function name
Add Function DeclarationInserts the member function declaration that matches the member function definition into the class declaration. The function can be public, protected, private, public slot, protected slot, or private slot.Function name
Add Class MemberAdds a member declaration for the class member being initialized if it is not yet declared. If Qt Creator cannot automatically detect the data type of the member, you must add it.Identifier
Create Implementations for Member FunctionsCreates implementations for all member functions in one go. In the Member Function Implementations dialog, specify whether the member functions are generated inline or outside the class.Function name
Switch with Next/Previous ParameterMoves a parameter down or up one position in a parameter list.Parameter in the declaration or definition of a function
Extract FunctionMoves the selected code to a new function and replaces the block of code with a call to the new function. Enter a name for the function in the Extract Function Refactoring dialog.Block of code selected
Extract Constant as Function ParameterReplaces the selected literal and all its occurrences with the function parameter newParameter. The parameter newParameter will have the original literal as the default value.Block of code selected
Add Local DeclarationAdds the type of an assignee, if the type of the right-hand side of the assignment is known. For example, rewrites
a = foo();

as

Type a = foo();

where Type is the return type of foo()

Assignee
Convert to Camel CaseConverts a symbol name to camel case, where elements of the name are joined without delimiter characters and the initial character of each element is capitalized. For example, rewrites an_example_symbol as anExampleSymbol and AN_EXAMPLE_SYMBOL as AnExampleSymbolIdentifier
Complete Switch StatementAdds all possible cases to a switch statement of the type enumswitch
Generate Missing Q_PROPERTY MembersAdds missing members to a Q_PROPERTY:
  • read function
  • write function, if there is a WRITE
  • onChanged signal, if there is a NOTIFY
  • data member with the name m_<propertyName>
Q_PROPERTY
Generate Q_PROPERTY and Missing MembersGenerates a Q_PROPERTY and adds missing members to it, as described above.Class member
Generate Constant Q_PROPERTY and Missing MembersGenerates a constant Q_PROPERTY and adds missing members to it, as described above.Class member
Generate Q_PROPERTY and Missing Members with Reset FunctionGenerates a Q_PROPERTY and adds missing members to it, as described above, but with an additional reset function.Class member
Apply ChangesKeeps function declarations and definitions synchronized by checking for the matching declaration or definition when you edit a function signature and by applying the changes to the matching code.Function signature. When this fix is available, a light bulb icon appears:
Add #include for undeclared or forward declared identifierAdds an #include directive to the current file to make the definition of a symbol available.Undeclared identifier
Add Forward DeclarationAdds a forward declaration for an undeclared identifier operation.Undeclared identifier
Reformat Pointers or ReferencesReformats declarations with pointers or references according to the code style settings for the current project. In case no project is open, the current global code style settings are used.

For example, rewrites:

char*s;

as

char *s;

When applied to selections, all suitable declarations in the selection are rewritten.

Declarations with pointers or references and selections that have such declarations
Create Getter and Setter Member FunctionsCreates either both getter and setter member functions for member variables or only a getter or setter.Member variable in class definition
Generate Getter and SetterCreates getter and setter member functions for a member variable.Member variable in class definition
Generate GetterCreates a getter member function for a member variable.Member variable in class definition
Generate SetterCreates a setter member function for a member variable.Member variable in class definition
Generate ConstructorCreates a constructor for a class.Class definition
Move Function DefinitionMoves a function definition to the implementation file, outside the class or back to its declaration. For example, rewrites:
class Foo
{
  void bar()
  {
      // do stuff here
  }
};

as

class Foo
{
  void bar();
};

void Foo::bar() {
    // do stuff here
}
Function signature
Move All Function DefinitionsMoves all function definitions to the implementation file or outside the class. For example, rewrites:
class Foo
{
  void bar()
  {
      // do stuff here
  }
  void baz()
  {
      // do stuff here
  }
};

as

class Foo
{
  void bar();
  void baz();
};

void Foo::bar() {
    // do stuff here
}

void Foo::baz() {
    // do stuff here
}
Class name
Move Definition HereMoves an existing function definition to its declaration.Function declaration
Assign to Local VariableAdds a local variable which stores the return value of a function call or a new expression. For example, rewrites:
QString s;
s.toLatin1();

as

QString s;
QByteArray latin1 = s.toLatin1();

and

new Foo;

as

Foo * localFoo = new Foo;

By default, Qt Creator uses the auto variable type when creating the variable. To label the variable with its actual type, select Preferences > C++ > Quick Fixes, and then deselect the Use type "auto" when creating new variables check box.

Function call or class name
Insert Virtual Functions of Base ClassesInserts declarations and the corresponding definitions inside or outside the class or in an implementation file (if it exists). For more information, see Insert virtual functions.Class or base class name
Optimize for-LoopRewrites post increment operators as pre increment operators and post decrement operators as pre decrement operators. It also moves other than string or numeric literals and id expressions from the condition of a for loop to its initializer. For example, rewrites:
for (int i = 0; i < 3 * 2; i++)

as

for (int i = 0, total = 3 * 2; i < total; ++i)
for
Escape String Literal as UTF-8Escapes non-ASCII characters in a string literal to hexadecimal escape sequences. String Literals are handled as UTF-8.String literal
Unescape String Literal as UTF-8Unescapes octal or hexadecimal escape sequences in a string literal. String Literals are handled as UTF-8.String literal
Convert to Stack VariableConverts the selected pointer to a stack variable. For example, rewrites:
QByteArray *foo = new QByteArray("foo");
foo->append("bar");

as

QByteArray foo("foo");
foo.append("bar");

This operation is limited to work only within function scope. Also, the coding style for pointers and references is not respected yet.

Pointer Variable
Convert to PointerConverts the selected stack variable to a pointer. For example, rewrites:
QByteArray foo = "foo";
foo.append("bar");

as

QByteArray *foo = new QByteArray("foo");
foo->append("bar");

This operation is limited to work only within function scope. Also, the coding style for pointers and references is not respected yet.

Stack Variable
Remove using namespace and Adjust Type Names AccordinglyRemove occurrences of using namespace in the local scope and adjust type names accordingly.using directive
Remove All Occurrences of using namespace in Global Scope and Adjust Type Names AccordinglyRemove all occurrences of using namespace in the global scope and adjust type names accordingly.using directive
Convert connect() to Qt 5 StyleConverts a Qt 4 QObject::connect() to Qt 5 style.QObject::connect() (Qt 4 style)
Convert Comment to C/C++ StyleConverts C-style comments into C++-style comments, and vice versa. Tries to preserve pretty layout and takes Doxygen and qdoc formatting into consideration, but you might need to clean up the results.Code comment
Move Function Documentation to Declaration/DefinitionMoves the documentation comment for a function between its declaration and definition.Documentation comment for a function

See also Apply quick fixes, Find symbols, Rename symbols, Specify settings for quick fixes, QML Quick Fixes, and Quick Fixes.

Reference

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