Conditionals

Gran parte della sintassi di Rust ti sarà familiare da C, C++ o Java:

  • Blocks are delimited by curly braces.
  • I commenti di riga iniziano con //, i commenti di blocco sono delimitati da /\* ... \*/.
  • Parole chiave come if e while funzionano allo stesso modo.
  • L’assegnazione delle variabili viene eseguita con =, il confronto viene eseguito con ==.

if expressions

You use if expressions exactly like if statements in other languages:

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In addition, you can use if as an expression. The last expression of each block becomes the value of the if expression:

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Speaker Notes

 This slide should take about 5 minutes.

Because if is an expression and must have a particular type, both of its branch blocks must have the same type. Show what happens if you add ; after "small" in the second example.

When if is used in an expression, the expression must have a ; to separate it from the next statement. Remove the ; before println! to see the compiler error.