Error map

expected primary-expression before C++: error: expected primary-expression before ')' token

C/C++ · layer 4, Application & API

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Centre: this error. First ring: errors it is linked with (9). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.

expected primary-expression before — C++: error: expected primary-expression before ')' token (C/C++)expected pr…was not declared in this scope — C++: error: 'x' was not declared in this scope (undeclared identifier) (C/C++)was not declared in…stray in program — C/C++: error: stray '\342' in program (smart quotes or invisible characters) (C/C++)stray in programexpected unqualified-id before — C++: error: expected unqualified-id before 'return' / before ')' token (C/C++)expected unqualifie…does not name a type — C++: error: 'string' does not name a type (C/C++)does not name a typeE0308 — Rust: error[E0308]: mismatched types — expected `X`, found `Y` (Rust)E0308expected ';' before — C/C++: error: expected ';' before 'x' — missing semicolon (C/C++)expected ';' beforedeclared and not used — Go: declared and not used: x / "fmt" imported and not used (Go)declared and not us…no matching function for call to — C++: error: no matching function for call to 'f(int, const char*)' (C/C++)no matching functio…need typename before dependent name — C++: error: need 'typename' before 'T::iterator' because 'T' is a dependent scope (C/C++)need typename befor…undefined reference to — C/C++: undefined reference to `function' — collect2: error: ld returned 1 exit status (C/C++)undefined reference…not a member of std — C++: error: 'optional' in namespace 'std' does not name a template type — wrong -std standard (C/C++)not a member of stdimplicit declaration of function — C: warning: implicit declaration of function 'foo' [-Wimplicit-function-declaration] (C/C++)implicit declaratio…call of overloaded is ambiguous — C++: error: call of overloaded 'f(int)' is ambiguous (C/C++)call of overloaded …cannot declare variable to be of abstract type — C++: error: cannot declare variable 'x' to be of abstract type 'Shape' (pure virtual functions) (C/C++)cannot declare vari…invalid conversion from — C++: error: invalid conversion from 'const char*' to 'char*' [-fpermissive] (C/C++)invalid conversion …incomplete type — C++: error: invalid use of incomplete type 'class X' — forward declaration only (C/C++)incomplete typenarrowing conversion — C++: error: narrowing conversion of 'x' from 'int' to 'char' inside { } [-Wnarrowing] (C/C++)narrowing conversionAttributeError — AttributeError: 'X' object has no attribute 'y' (Python)AttributeErrorClassCastException — java.lang.ClassCastException: class A cannot be cast to class B (Java)ClassCastExceptionTS7016 — TS7016: Could not find a declaration file for module 'x'. 'x.js' implicitly has an 'any' type. (Node.js)TS7016TypeError: not a function — TypeError: x is not a function (JavaScript)TypeError: not a fu…ImportError — ImportError: cannot import name 'x' from 'y' (Python)ImportErrornot a constructor — TypeError: x is not a constructor (JavaScript)not a constructorno match for 'operator' — C++: error: no match for 'operator<<' (operand types are 'std::ostream' and 'X') (C/C++)no match for 'opera…use of deleted function — C++: error: use of deleted function 'X::X(const X&)' — copying a non-copyable type (C/C++)use of deleted func…template argument deduction/substitution failed — C++: error: template argument deduction/substitution failed / couldn't deduce template parameter (C/C++)template argument d…

Directly related (9)

was not declared in this scopeC/C++

C++: error: 'x' was not declared in this scope (undeclared identifier)

The compiler met a name it has never seen: it is misspelled, declared later, out of scope, or its header or namespace is missing.

stray in programC/C++

C/C++: error: stray '\342' in program (smart quotes or invisible characters)

The source file contains a character the compiler does not recognise, typically curly quotes or a non-breaking space pasted from…

expected unqualified-id beforeC/C++

C++: error: expected unqualified-id before 'return' / before ')' token

The parser found a token where a name (declaration) was required — often a missing brace, a stray `)`, or a statement placed in a…

does not name a typeC/C++

C++: error: 'string' does not name a type

Where the compiler expected a type, it found a name it does not know as one — a missing header, namespace, or class declared late…

E0308Rust

Rust: error[E0308]: mismatched types — expected `X`, found `Y`

A value’s type doesn’t match what the context expects — common with &str vs String, Option/Result vs plain values, and integer ty…

expected ';' beforeC/C++

C/C++: error: expected ';' before 'x' — missing semicolon

The compiler reached a token where a statement should have ended — almost always a missing semicolon on the line above.

declared and not usedGo

Go: declared and not used: x / "fmt" imported and not used

Go refuses to compile code with unused local variables or unused imports.

no matching function for call toC/C++

C++: error: no matching function for call to 'f(int, const char*)'

No overload of the function accepts the arguments you passed — wrong count, wrong types, or a missing conversion.

need typename before dependent nameC/C++

C++: error: need 'typename' before 'T::iterator' because 'T' is a dependent scope

Inside a template, a name like `T::iterator` could be a type or a value, so C++ requires the `typename` keyword to say it is a ty…

Two steps away (17)

undefined reference toC/C++

C/C++: undefined reference to `function' — collect2: error: ld returned 1 exit status

The linker can’t find the definition of a function or variable that was declared and used.

not a member of stdC/C++

C++: error: 'optional' in namespace 'std' does not name a template type — wrong -std standard

The standard-library feature you used needs a newer C++ standard than the compiler is currently set to.

implicit declaration of functionC/C++

C: warning: implicit declaration of function 'foo' [-Wimplicit-function-declaration]

In C you called a function the compiler has not seen declared — usually a missing `#include`. Newer compilers treat it as an erro…

call of overloaded is ambiguousC/C++

C++: error: call of overloaded 'f(int)' is ambiguous

Two or more overloads fit equally well, so the compiler refuses to guess which function you meant.

cannot declare variable to be of abstract typeC/C++

C++: error: cannot declare variable 'x' to be of abstract type 'Shape' (pure virtual functions)

You tried to create an object of a class that still has pure virtual functions; only a derived class that overrides all of them c…

invalid conversion fromC/C++

C++: error: invalid conversion from 'const char*' to 'char*' [-fpermissive]

C++ forbids silently dropping `const` or converting between unrelated pointer types — typically a string literal assigned to `cha…

incomplete typeC/C++

C++: error: invalid use of incomplete type 'class X' — forward declaration only

You used a class that has only been forward-declared (so its size and members are unknown) where the full definition is required.

narrowing conversionC/C++

C++: error: narrowing conversion of 'x' from 'int' to 'char' inside { } [-Wnarrowing]

Brace initialisation `{}` refuses conversions that can lose data, such as `double` to `int` or a runtime `int` to `char`.

AttributeErrorPython

AttributeError: 'X' object has no attribute 'y'

You accessed an attribute or method that doesn’t exist on that object type.

ClassCastExceptionJava

java.lang.ClassCastException: class A cannot be cast to class B

An object was cast to a type it isn’t.

TS7016Node.js

TS7016: Could not find a declaration file for module 'x'. 'x.js' implicitly has an 'any' type.

The JavaScript package has no TypeScript types bundled and no @types package installed.

TypeError: not a functionJavaScript

TypeError: x is not a function

You called something as a function, but its value is not a function (it’s undefined, a string, an object…).

ImportErrorPython

ImportError: cannot import name 'x' from 'y'

The module was found, but the name you’re importing from it doesn’t exist — usually a version change or a circular import.

not a constructorJavaScript

TypeError: x is not a constructor

new was used with something that isn’t a class/constructor — usually a wrong import.

no match for 'operator'C/C++

C++: error: no match for 'operator<<' (operand types are 'std::ostream' and 'X')

You used an operator on a type that does not define it — most often printing your own class with `

use of deleted functionC/C++

C++: error: use of deleted function 'X::X(const X&)' — copying a non-copyable type

The code needs a function (usually a copy constructor or assignment) that was deleted explicitly or implicitly, as for `std::uniq…

template argument deduction/substitution failedC/C++

C++: error: template argument deduction/substitution failed / couldn't deduce template parameter

The compiler could not work out the template arguments from your call — the arguments disagree, the type can't be deduced, or a c…