Type compatibility NameLanguage'null' is not compatible with parameter's declared type PHPArithmetic operation with unsupported operands PHPArray offset access on illegal type PHPIllegal array key type PHPIllegal string offset PHPIncompatible return type PHPInvalid argument supplied for 'foreach()' PHPMissing parameter's type declaration PHPMissing property's type declaration PHPMissing return type declaration PHPMissing strict types declaration PHPParameter type PHPRedundant intersection type PHPStrict type checking rules violation PHPType declaration is redundant and could be simplified PHPType mismatch in property assignment PHP Last modified: 13 July 2023 Assignment can be replaced with operator assignment 'null' is not compatible with parameter's declared type