X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FFunction%2FParameters.pm;h=1eeae0518532bf97ab69c379d9d756406869c103;hb=7817d698ba4e55c46484533c96bd45ee8b02e502;hp=0f4a82d578cbdb186b5dd8ad26e39c58ef4a9ace;hpb=7947f7ce418bbcde81608456917b72252b4c1934;p=p5sagit%2FFunction-Parameters.git diff --git a/lib/Function/Parameters.pm b/lib/Function/Parameters.pm index 0f4a82d..1eeae05 100644 --- a/lib/Function/Parameters.pm +++ b/lib/Function/Parameters.pm @@ -5,14 +5,14 @@ use v5.14.0; use strict; use warnings; +use Carp qw(confess); + use XSLoader; BEGIN { - our $VERSION = '0.05_03'; + our $VERSION = '0.06'; XSLoader::load; } -use Carp qw(confess); - sub _assert_valid_identifier { my ($name, $with_dollar) = @_; my $bonus = $with_dollar ? '\$' : ''; @@ -28,13 +28,32 @@ sub _assert_valid_attributes { my @bare_arms = qw(function method); my %type_map = ( - function => { name => 'optional' }, + function => { + name => 'optional', + default_arguments => 1, + check_argument_count => 0, + }, method => { name => 'optional', - shift => '$self', + default_arguments => 1, + check_argument_count => 0, attrs => ':method', + shift => '$self', + }, + classmethod => { + name => 'optional', + default_arguments => 1, + check_argument_count => 0, + attributes => ':method', + shift => '$class', }, ); +for my $k (keys %type_map) { + $type_map{$k . '_strict'} = { + %{$type_map{$k}}, + check_argument_count => 1, + }; +} sub import { my $class = shift; @@ -56,34 +75,53 @@ sub import { ? $proto : [$proto, $bare_arms[$bare++] || confess(qq{Don't know what to do with "$proto"})] ; - my ($name, $type) = @$item; + my ($name, $proto_type) = @$item; _assert_valid_identifier $name; - unless (ref $type) { - # use '||' instead of 'or' to preserve $type in the error message - $type = $type_map{$type} - || confess qq["$type" doesn't look like a valid type (one of ${\join ', ', sort keys %type_map})]; + unless (ref $proto_type) { + # use '||' instead of 'or' to preserve $proto_type in the error message + $proto_type = $type_map{$proto_type} + || confess qq["$proto_type" doesn't look like a valid type (one of ${\join ', ', sort keys %type_map})]; } - $type->{name} ||= 'optional'; - $type->{name} =~ /^(?:optional|required|prohibited)\z/ - or confess qq["$type->{name}" doesn't look like a valid name attribute (one of optional, required, prohibited)]; - $type->{shift} and _assert_valid_identifier $type->{shift}, 1; - $type->{attrs} and _assert_valid_attributes $type->{attrs}; + my %type = %$proto_type; + my %clean; + + $clean{name} = delete $type{name} || 'optional'; + $clean{name} =~ /^(?:optional|required|prohibited)\z/ + or confess qq["$clean{name}" doesn't look like a valid name attribute (one of optional, required, prohibited)]; + + $clean{shift} = delete $type{shift} || ''; + _assert_valid_identifier $clean{shift}, 1 if $clean{shift}; + + $clean{attrs} = join ' ', map delete $type{$_} || (), qw(attributes attrs); + _assert_valid_attributes $clean{attrs} if $clean{attrs}; - $spec{$name} = $type; + $clean{default_arguments} = + exists $type{default_arguments} + ? !!delete $type{default_arguments} + : 1 + ; + $clean{check_argument_count} = !!delete $type{check_argument_count}; + + %type and confess "Invalid keyword property: @{[keys %type]}"; + + $spec{$name} = \%clean; } for my $kw (keys %spec) { my $type = $spec{$kw}; - $^H{HINTK_SHIFT_ . $kw} = $type->{shift} || ''; - $^H{HINTK_ATTRS_ . $kw} = $type->{attrs} || ''; - $^H{HINTK_NAME_ . $kw} = - $type->{name} eq 'prohibited' ? FLAG_NAME_PROHIBITED : - $type->{name} eq 'required' ? FLAG_NAME_REQUIRED : - FLAG_NAME_OPTIONAL + my $flags = + $type->{name} eq 'prohibited' ? FLAG_ANON_OK : + $type->{name} eq 'required' ? FLAG_NAME_OK : + FLAG_ANON_OK | FLAG_NAME_OK ; + $flags |= FLAG_DEFAULT_ARGS if $type->{default_arguments}; + $flags |= FLAG_CHECK_NARGS if $type->{check_argument_count}; + $^H{HINTK_FLAGS_ . $kw} = $flags; + $^H{HINTK_SHIFT_ . $kw} = $type->{shift}; + $^H{HINTK_ATTRS_ . $kw} = $type->{attrs}; $^H{+HINTK_KEYWORDS} .= "$kw "; } } @@ -106,6 +144,8 @@ sub unimport { __END__ +=encoding UTF-8 + =head1 NAME Function::Parameters - subroutine definitions with parameter lists @@ -114,10 +154,12 @@ Function::Parameters - subroutine definitions with parameter lists use Function::Parameters; + # simple function fun foo($bar, $baz) { return $bar + $baz; } + # function with prototype fun mymap($fun, @args) :(&@) { my @res; for (@args) { @@ -128,14 +170,26 @@ Function::Parameters - subroutine definitions with parameter lists print "$_\n" for mymap { $_ * 2 } 1 .. 4; + # method with implicit $self method set_name($name) { $self->{name} = $name; } + # function with default arguments + fun search($haystack, $needle = qr/^(?!)/, $offset = 0) { + ... + } + + # method with default arguments + method skip($amount = 1) { + $self->{position} += $amount; + } + =cut =pod + # use different keywords use Function::Parameters { proc => 'function', meth => 'method', @@ -166,7 +220,7 @@ list consists of comma-separated variables. The effect of C is as if you'd written C, i.e. the parameter list is simply -copied into C and initialized from L<@_|perlvar/"@_">. +copied into L and initialized from L<@_|perlvar/"@_">. In addition you can use C, which understands the same syntax as C but automatically creates a C<$self> variable for you. So by writing @@ -176,18 +230,30 @@ C. =head2 Customizing the generated keywords You can customize the names of the keywords injected into your scope. To do -that you pass a hash reference in the import list: +that you pass a reference to a hash mapping keywords to types in the import +list: + + use Function::Parameters { + KEYWORD1 => TYPE1, + KEYWORD2 => TYPE2, + ... + }; + +Or more concretely: use Function::Parameters { proc => 'function', meth => 'method' }; # -or- use Function::Parameters { proc => 'function' }; # -or- - use Function::Parameters { meth => 'method' }; + use Function::Parameters { meth => 'method' }; # etc. The first line creates two keywords, C and C (for defining functions and methods, respectively). The last two lines only create one -keyword. Generally the hash keys can be any identifiers you want while the -values have to be either C, C, or a hash reference (see -below). The difference between C and C is that Cs -automatically L their first argument into C<$self>. +keyword. Generally the hash keys (keywords) can be any identifiers you want +while the values (types) have to be either a hash reference (see below) or +C<'function'>, C<'method'>, C<'classmethod'>, C<'function_strict'>, +C<'method_strict'>, or C<'classmethod_strict'>. The main difference between +C<'function'> and C<'method'> is that C<'method'>s automatically +L their first argument into C<$self> (C<'classmethod'>s +are similar but shift into C<$class>). The following shortcuts are available: @@ -200,7 +266,7 @@ The following shortcuts are available: =pod The following shortcuts are deprecated and may be removed from a future version -of the module: +of this module: # DEPRECATED use Function::Parameters 'foo'; @@ -219,8 +285,8 @@ of the module: That is, if you want to pass arguments to L, use a hashref, not a list of strings. -You can customize things even more by passing a hashref instead of C -or C. This hash can have the following keys: +You can customize the properties of the generated keywords even more by passing +a hashref instead of a string. This hash can have the following keys: =over @@ -237,13 +303,13 @@ Valid values: strings that look like a scalar variable. Any function created by this keyword will automatically L its first argument into a local variable whose name is specified here. -=item C +=item C, C Valid values: strings that are valid source code for attributes. Any value specified here will be inserted as a subroutine attribute in the generated code. Thus: - use Function::Parameters { sub_l => { attrs => ':lvalue' } }; + use Function::Parameters { sub_l => { attributes => ':lvalue' } }; sub_l foo() { ... } @@ -254,11 +320,103 @@ turns into ... } +It is recommended that you use C in new code but C is also +accepted for now. + +=item C + +Valid values: booleans. This property is on by default, so you have to pass +C<< default_arguments => 0 >> to turn it off. If it is disabled, using C<=> in +a parameter list causes a syntax error. Otherwise it lets you specify +default arguments directly in the parameter list: + + fun foo($x, $y = 42, $z = []) { + ... + } + +turns into + + sub foo { + my ($x, $y, $z) = @_; + $y = 42 if @_ < 2; + $z = [] if @_ < 3; + ... + } + +except that none of the parameters are in scope in the expressions that specify +default values. Thus: + + my $var = "outer"; + + fun foo($var, $wat = $var) { + # $wat will default to "outer", not to what was passed + # as the first argument! + ... + } + +This may change in a future version of this module. + +=item C + +Valid values: booleans. This property is off by default. If it is enabled, the +generated code will include checks to make sure the number of passed arguments +is correct (and otherwise throw an exception via L): + + fun foo($x, $y = 42, $z = []) { + ... + } + +turns into + + sub foo { + Carp::croak "Not enough arguments for fun foo" if @_ < 1; + Carp::croak "Too many arguments for fun foo" if @_ > 3; + my ($x, $y, $z) = @_; + $y = 42 if @_ < 2; + $z = [] if @_ < 3; + ... + } + =back -Plain C<'function'> is equivalent to C<< { name => 'optional' } >>, and plain -C<'method'> is equivalent to -C<< { name => 'optional', shift => '$self', attrs => ':method' } >>. +Plain C<'function'> is equivalent to: + + { + name => 'optional', + default_arguments => 1, + check_argument_count => 0, + } + +(These are all default values so C<'function'> is also equivalent to C<{}>.) + +C<'function_strict'> is like C<'function'> but with +C<< check_argument_count => 1 >>. + +C<'method'> is equivalent to: + + { + name => 'optional', + default_arguments => 1, + check_argument_count => 0, + attributes => ':method', + shift => '$self', + } + +C<'method_strict'> is like C<'method'> but with +C<< check_argument_count => 1 >>. + +C<'classmethod'> is equivalent to: + + { + name => 'optional', + default_arguments => 1, + check_argument_count => 0, + attributes => ':method', + shift => '$class', + } + +C<'classmethod_strict'> is like C<'classmethod'> but with +C<< check_argument_count => 1 >>. =head2 Syntax and generated code @@ -268,12 +426,12 @@ of C, parsing it as C<$bar-Efoo([1], $bar[0])>. Yes. You can add parens to change the interpretation of this code, but C will only trigger a I warning. This module attempts -to fix all of this by adding a subroutine declaration before the definition, +to fix all of this by adding a subroutine declaration before the function body, so the parser knows the name (and possibly prototype) while it processes the body. Thus C really turns into -C. +C. -If you need L, you can +If you need L, you can put them after the parameter list with their usual syntax. Syntactically, these new parameter lists live in the spot normally occupied @@ -282,17 +440,23 @@ specifying it as the first attribute (this is syntactically unambiguous because normal attributes have to start with a letter while a prototype starts with C<(>). -As an example, the following declaration uses every feature available -(subroutine name, parameter list, prototype, attributes, and implicit -C<$self>): +As an example, the following declaration uses every available feature +(subroutine name, parameter list, default arguments, prototype, default +attributes, attributes, argument count checks, and implicit C<$self>): - method foo($x, $y, @z) :($;$@) :lvalue :Banana(2 + 2) { + method foo($x, $y, $z = sqrt 5) :($$$;$) :lvalue :Banana(2 + 2) { ... } And here's what it turns into: - sub foo ($;$@); sub foo ($;$@) :lvalue :Banana(2 + 2) { my $self = shift; my ($x, $y, @z) = @_; + sub foo ($$$;$) :method :lvalue :Banana(2 + 2) { + sub foo ($$$;$); + Carp::croak "Not enough arguments for method foo" if @_ < 2; + Carp::croak "Too many arguments for method foo" if @_ > 4; + my $self = shift; + my ($x, $y, $z) = @_; + $z = sqrt 5 if @_ < 3; ... } @@ -306,7 +470,12 @@ Another example: And the generated code: - my $coderef = sub (;$$) :lvalue :Gazebo((>:O)) { my ($p, $q) = @_; + my $coderef = sub (;$$) :lvalue :Gazebo((>:O)) { + # vvv only if check_argument_count is enabled vvv + Carp::croak "Not enough arguments for fun (anon)" if @_ < 2; + Carp::croak "Too many arguments for fun (anon)" if @_ > 2; + # ^^^ ^^^ + my ($p, $q) = @_; ... }; @@ -314,13 +483,14 @@ And the generated code: If you want to wrap L, you just have to call its C method. It always applies to the file that is currently being parsed -and its effects are lexical (i.e. it works like L or L): +and its effects are L (i.e. it works like L or +L). package Some::Wrapper; use Function::Parameters (); sub import { Function::Parameters->import; - # or Function::Parameters->import(@other_import_args); + # or Function::Parameters->import(@custom_import_args); } =head1 AUTHOR