Perl Learning One: Exploring the Perl World

1.PERL4 Kinds of variables

Scalar: $ pure variable, scalar
Array: @
Hash:%
File: Uppercase

2. Variable composition

1. Naming rules case sensitive, alphanumeric underline ...
2. No keywords, $+ other, but can not conflict with built-in variables.
3. The name length is infinite.

3. In pure variables: integer, float, character, string,
Integer variable
1. You can use _ to divide character numbers
2.012 is octal 10
3.0X1F is 16 binary
Floating-point variable
1.11.4
2.-0.3
3..3
can represent a 15-bit valid number, truncated after 16 bits.
The precision of floating-point numbers

Perl Learning One: Exploring the Perl World