ifs vs mappings in UniswapConfig.sol

[RickieRao]

Hi guys, great work, I am currently checking out the contracts code,

and wondering if it is better to have many if conditions like:

function getUnderlyingIndex(address underlying) internal view returns (uint) {
if (underlying == underlying00) return 0;
if (underlying == underlying01) return 1;
if (underlying == underlying02) return 2;
if (underlying == underlying03) return 3;
if (underlying == underlying04) return 4;
if (underlying == underlying05) return 5;
if (underlying == underlying06) return 6;
...

for underlying, symbols, cTokens
than having mappings like(pseudo-code here):

underlyingAddress => TokenConfig;
symbols => TokenConfig;
cTokenAddress => TokenConfig;

i mean using ifs means you will need to go through 0 - 5 to get the 06 index every time right?

I'm just green in solidity coding, so hoping to get some insights here.

Many thanks.

[coburncoburn]

in order to use immutable values rather than storage reads, the if statements are necessary. This makes for lower gas costs