Description: Define the restriction function. See brrestrict for its value. (Contributed by Scott Fenton, 17-Apr-2014)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-restrict | |- Restrict = ( Cap o. ( 1st (x) ( Cart o. ( 2nd (x) ( Range o. 1st ) ) ) ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 0 | crestrict | |- Restrict | |
| 1 | ccap | |- Cap | |
| 2 | c1st | |- 1st | |
| 3 | ccart | |- Cart | |
| 4 | c2nd | |- 2nd | |
| 5 | crange | |- Range | |
| 6 | 5 2 | ccom | |- ( Range o. 1st ) | 
| 7 | 4 6 | ctxp | |- ( 2nd (x) ( Range o. 1st ) ) | 
| 8 | 3 7 | ccom | |- ( Cart o. ( 2nd (x) ( Range o. 1st ) ) ) | 
| 9 | 2 8 | ctxp | |- ( 1st (x) ( Cart o. ( 2nd (x) ( Range o. 1st ) ) ) ) | 
| 10 | 1 9 | ccom | |- ( Cap o. ( 1st (x) ( Cart o. ( 2nd (x) ( Range o. 1st ) ) ) ) ) | 
| 11 | 0 10 | wceq | |- Restrict = ( Cap o. ( 1st (x) ( Cart o. ( 2nd (x) ( Range o. 1st ) ) ) ) ) |