if and switch

if and switch
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Syntax

if ( expr ) statement if ( expr ) then statement_list end if ( expr ) then statement_list else statement_list end if ( expr ) then statement_list elif ( expr ) statement if ( expr ) then statement_list elif ( expr ) then statement_list end if ( expr ) then statement_list elif ( expr ) then statement_list else statement_list end switch ( expr ) case expr: statement_list case expr: statement_list default: statement_list end

if

The short form of the if statement, which must be typed on one line, dispenses with the then keyword and accepts a single statement to be executed if expr evaluates as true.

The long form uses a then keyword and allows optional else and elif clauses. The last if in an elif chain may be either a short- or a long-form if statement.

Where an expression is expected, conventional high level language syntax is accepted. Names refer to variables, * means multiply, not wildcard and > means greater than, not i/o redirection.

switch

In a switch statement, expressions are compared by pattern match, as if using the =~ comparison operator. The case expression can be a string with wildcard characters. Comparisons are made down the list of alternatives until one matches. All following statements are executed until a break is encountered. A default clause is optional but is always satisfied if no other case matches.