swift - Making a variable from if statement global -

while encoding json, i´m unwrapping stuff if let statement, i'd make variable globally available

do {   if     let json = try jsonserialization.jsonobject(with: data) as? [string: string],      let jsonisexistant = json["isexistant"]    {     // here make jsonisexistant globally available   } 

is possible? if isn't, make if statement inside of one, don't think clever or possible.

delclare jsonisexistant @ place want it. if making ios app, above viewdidload() create variable

var jsonisexistant: string? 

then @ point use it

do {     if let json = try jsonserialization.jsonobject(with: data) as? [string: string],      let tempjsonisexistant = json["isexistant"] {         jsonisexistant = tempjsonisexistant     } } 

this rewritten though

do {     if let json = try jsonserialization.jsonobject(with: data) as? [string: string] {          jsonisexistant = json["isexistant"]     } } catch {     //handle error } 

if handled second way, have check if jsonisexistant nil before use, or unwrap ! if sure have field "isexistant" every time succeeds @ becoming json.