Rascal/Expressions/Values/List/Append

Name Rascal/Expressions/Values/List/Append

Synopsis Append an element at the end of a list

Syntax Exp₁ + Exp₂

Types

`Exp₁`	`Exp₂`	`Exp₁ + Exp₂`
`list[T₁]`	`T₂`	`list[lub(T₁,T₂)]`

Description The operator + appends an element at the end of a list. The + is one of those Operators which are overloaded. It can also mean List/Insert or List/Concatenation for example.

Examples

rascal>[] + 1;
list[int]: [1]
rascal>[1] + 2;
list[int]: [1,2]

Pitfalls

If both operands of + are a list, then it acts as List/Concatenation This is concatenation:
```
rascal>[1] + [2]
list[int]: [1,2]
```
To append a list to a list, use extra brackets:
```
rascal>[1] + [[2]]
list[value]: [
  1,
  [2]
]
```

Questions

Question [1].

When you append an element to a list, the number of elements in the result is always:

Question [2].

Question [3].

["Obi-Wan Kenobi"] + "Bruno" ==

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