Hello 7stud,

Consider the following:

16:46 >raku -e "for 1 .. * { qq[$_ is { $_.^name }].put; last if $_ >=
+ 3; }"
1 is Int
2 is Int
3 is Int

16:46 >

[download]

$_ is the topic variable which, as in Perl, acts like a pronoun: we can read the code as “for each value from 1 to infinity, print it and its type, ...” The topic variable $_ is documented in https://docs.raku.org/language/variables#The_$__variable.

The star, on the other hand, is not a variable, but rather an object — specifically, an instance of Raku’s built-in Whatever class. Its meaning depends on the context in which it is used. In this case it is being used as the end-point of a range, so its meaning is defined by the Range class, which interprets it as Inf (infinity). This use of the star in Raku is documented in https://docs.raku.org/type/Whatever.

So although $_ and * can sometimes be used interchangeably, they are in fact quite different things.

Hope that helps,

Athanasius <°(((>< contra mundum סתם עוד האקר של פרל,

In reply to Re: Raku: * v. $_ (asterisk v. the topic variable) by Athanasius
in thread Raku: * v. $_ (asterisk v. the topic variable) by 7stud

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