$a = something;  # something is executed in a scalar context.
@a = something;  # something is executed in a list   context.
something;       # something is executed in a void   context.

# Arrays return their number of elements in a scalar context:
@b = qw( a b c );
print(       @b , "\n");   # abc
print(scalar(@b), "\n");   # 3
# print accepts a list, but scalar() forced scalar context.

# Arithmetic forces scalar context:
print(@b,"\n");            # abc
print(@b."\n");            # 3

# Not just string arithmetic:
print(@b,   "\n");         # abc
print(@b+0, "\n");         # 3

# Functions can examine their context:
{
   local $, = ", ";
   local $\ = "\n";
   print(       localtime );  # 59, 14, 15, 1, 9, 104, 5, 274, 1
   print(scalar(localtime));  # Fri Oct  1 15:05:32 2004
}
# Refer to wantarray in perlfunc.

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In reply to scalar vs list context by ikegami
in thread while loop, search & replace by PJT

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