parrotcode undef PMC
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src/pmc/undef.pmc

NAME

src/pmc/undef.pmc - Generic undefined value

DESCRIPTION

This is Parrot's generic undef type. This PMC has no defined value. It returns a numeric value of 0, a boolean of false, and an empty string. When assigned a number, integer, or string it morphs to a Number, Integer, or String PMC respectively, and when assigned a generic PMC it morphs into a PMC of the passed-in type and does a same-type assignment from there.

Methods

void set_pmc(PMC *other): Sets the current PMC to *other by first changing the current PMC to the appropriate type.
void assign_pmc(PMC *other): Assigns the PMC to the value of *other by first changing the PMC to the appropriate type.
INTVAL get_integer(): Returns 0.
INTVAL defined(): Returns 0.
void set_integer_native(INTVAL value): Morphs the current PMC to an Integer and sets the value from value.
FLOATVAL get_number(): Returns 0.0.
void set_number_native(FLOATVAL value): Morphs the current PMC to a Float and sets the value from value.
STRING *get_string(): Returns an empty string.
void set_string_native(STRING *value): Morphs the current PMC to a String and sets the value from value.
INTVAL get_bool(): Returns 0.
void share(): Unknown. (TODO)
PMC *share_ro(): Unknown. (TODO)
PMC *clone(): Clones the current Undef PMC.
INTVAL is_equal(PMC *value): Returns 1 if the *value is an Undef PMC, 0 otherwise.