Requires Perl to be at least this version and enables the feature bundle for this version. Requiring 5.12 or newer implicitly enables pragma strict.

version can be numeric like 5.005 or 5.008001, or a v-string like 5.8.1 or V5.14. Unfortunately, 5.14 is interpreted as 5.140.

With no, requires Perl to be older than the given version and doesn’t enable features.

Replaces built-in functions with ones that die upon failure.

Enables attributes.

Determines that the module will not be loaded until one of the named functions is called.

Establishes an IS-A relationship with the named classes at compile time.

Uses the Math::BigInt package to handle all integer calculations transparently.

options can be accuracy, precision, trace, version, and lib. One-letter abbreviations are allowed. Accuracy and precision require a numeric argument, and lib requires the name of a Perl module to handle the calculations.

Uses the Math::BigNum package to handle all numeric calculations transparently.

See bigint above for options.

Use the Math::BigNum and Math::BigRat packages to handle all numeric calculations transparently.

See bigint above for options.

Uses the MakeMaker’s uninstalled version of a package. dir defaults to the current directory. Used for testing of uninstalled packages.

Treats character data as strict 8-bit bytes, as opposed to Unicode UTF-8.

Enables character names to be expanded in strings using N escapes.

Defines name to represent a constant value.

Forces verbose warning diagnostics and suppression of duplicate warnings. If verbosity is -verbose, makes it even more verbose.

Sets the script encoding and pushes the encoding I/O layer for standard input and standard output. The second form allows you to select the I/O layers explicitly.

Issues warnings when a non-ASCII character is implicitly converted into UTF-8.

Enables features. See the section Features.

Implements compile-time verified class fields.

Changes the way the file test operators (page 47) get their information. Standard strategy is stat, alternative is access.

uses a module if a condition holds.

Enables integer arithmetic instead of double precision floating point.

Requests less of something (unimplemented).

Adds libraries to @INC, or removes them, at compile time.

Uses POSIX locales for built-in operations.

Use method resolution order type. Values are dfs (default) and c3.

Establishes default I/O layers for input and output.

Restricts unsafe operations when compiling.

Overloads Perl operators. operator is the operator (as a string), subref a reference to the subroutine handling the overloaded operator.

Lexically disable or enable overloading.

Establishes an IS-A relationship with the named classes at compile time.

Alters regular expression behavior. behaviors can be any combination of eval (allows patterns to contain assertions that execute Perl code, even when the pattern contains interpolated variables; see page 39), taint (propagates tainting), debug, and debugcolor (produce debugging info).

flags can be used to set default flags for regular expressions.

Enables simple signal handling. info is a list of signals, e.g., qw(SEGV TRAP).

Controls sort behavior. options can be stable to require stability, _quicksort (or _qsort) to use a quicksort algorithm, and _mergesort to use a mergesort algorithm.

Restricts unsafe constructs. constructs can be any combination of refs (restricts the use of symbolic references), vars (requires all variables to be either predefined by Perl, imported, globally or lexically scoped, or fully qualified), and subs (restricts the use of bareword identifiers that are not subroutines).

Predeclares subroutine names so you can use them without parentheses even before they are declared.

Enables the use of interpreter-based threads. See the section Threads.

Adds data sharing between threads.

Enables or disables UTF-8 (or UTF-EBCDIC) in source code.

Predeclares variable names, allowing you to use them even if they are not fully qualified under the strict pragma. Obsolete; use our (page 63) instead.

Provides support for version objects.

Controls VMS-specific language features. VMS only. features can be any combination of exit (enables VMS-style exit codes), status (allows system commands to deliver VMS-style exit codes to the calling program), and time (makes all times relative to the local time zone).

Controls built-in warnings for classes of conditions.

Creates a warnings category for the current package.