Symbol (programming) - Support - Smalltalk - Examples

Examples

The following is a simple example of a symbol literal in Smalltalk:

my_symbol := #'an identifier' " Symbol literal " my_symbol := #a " Technically, this is a selector literal. In most implementations, " " selectors are symbols, so this is also a symbol literal "

Strings can be coerced into symbols, vice versa:

my_symbol := 'Hello, world!' asSymbol " => #'Hello, world!' " my_string := #hello: asString " => 'hello:' "

Symbols conform to the symbol protocol, and their class is called Symbol in most implementations:

my_symbol := #hello_world my_symbol class " => Symbol "

Symbols are commonly used to dynamically send messages to (call methods on) objects:

" same as 'foo' at: 2 " 'foo' perform: #at: with: 2 " => $o "

Read more about this topic:  Symbol (programming), Support, Smalltalk

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