01_04_if.slide

# if

## if

syntax

    if <condition>{
        // do stuff
    }

comparison operators: **== != < <= > >=**

.play -numbers _concepts/01_introduction/04if/01if.go /^func main/,/^}/

.link https://go.dev/ref/spec#If_statements see specs


## if multiple conditions

    if <multiple conditions>{
        // do stuff
    }

    
logical operators: **&& || !**

examples: 

    if (a > b) && (i == j){}
    if !(a > b){}
    if a <= b{} // same as above not example

: for simplicity of the example, we are using empty curly parenthesis. but in real scenarios, we will have code within

.play -numbers _concepts/01_introduction/04if/02if.go /^func main/,/^}/


## else

syntax

    if <condition>{
        // do stuff
    }else{
        // do other stuff
    }

example

.play -numbers _concepts/01_introduction/04if/03else.go /^func main/,/^}/



## elseif

syntax

    if <condition>{
        // do stuff
    }else if <other condition>{
        // do other stuff
    }else{
        // do someother stuff
    }

example

.play -numbers _concepts/01_introduction/04if/04elseif.go /^func main/,/^}/


## quiz

## quiz
what is the output

.play -numbers _concepts/01_introduction/04if/05q1.go /^func main/,/^}/

: answer: syntax error. else should always start in the same line as the closing curly braces of the previous if/else-if block

## quiz
what is the output

.play -numbers _concepts/01_introduction/04if/05q2.go /^func main/,/^}/

: answer: "nothing is correct". the else case will be executed


## nested if

syntax:

    if <condition>{
        // do stuff
        if <condition>{
            // do stuff
        }
    }


.play -numbers _concepts/01_introduction/04if/06nestedif.go /^func main/,/^}/