Term unification

### 6.2 Term unification

#### 6.2.1 `(=)/2` - Prolog unification

Templates

  `=(?term, ?term)`

Description
`Term1 = Term2` unifies `Term1` and `Term2`. No occurs check is done, i.e. this predicate does not check if a variable is unified with a compound term containing this variable (this can lead to an infinite loop).
`=` is a predefined infix operator (section 6.14.10).
Errors
None.
Portability
ISO predicate.

#### 6.2.2 `unify_with_occurs_check/2`

Templates

  `unify_with_occurs_check(?term, ?term)`

Description
`unify_with_occurs_check(Term1, Term2)` unifies `Term1` and `Term2`. The occurs check test is done (i.e. the unification fails if a variable is unified with a compound term containing this variable).
Errors
None.
Portability
ISO predicate.

#### 6.2.3 `(``\``=)/2` - not Prolog unifiable

Templates

  `\``=(?term, ?term)`

Description
`Term1` `\``= Term2` succeeds if `Term1` and `Term2` are not unifiable (no occurs check is done).
`\``=` is a predefined infix operator (section 6.14.10).
Errors
None.
Portability
ISO predicate.

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