Any user can create a new pool by calling
BFactorycontract. The caller is set as the
controlleror pool owner.
Pools can exist in one of two states:
finalized. Pools start in a controlled state and the controller may choose to make the pool finalized by calling
finalize(). Finalize is a one-way transition. While in a controlled state, outside actors cannot add liquidity. A controlled state allows the controller to set the pool's tokens and weights.
All pools in Balancer are also ERC20 tokens known as BPTs (Balancer Pool Tokens), which represent proportional ownership in the pool's liquidity. When users add liquidity through
joinswap*they receive BPTs proportional to the amount of assets they are adding to the pool.
BPTs are an opinionated ERC20 token implementation, and have a few subtle differences.
transferFromfrom itself does not require a previous allowance.