lappend(n) Tcl Built-In Commands lappend(n)

```

```

# [NAME](#NAME)

lappend - Append list elements onto a variable

# [SYNOPSIS](#SYNOPSIS)

**lappend varName** ?*value ...*?

```

```

# [DESCRIPTION](#DESCRIPTION)

This command treats the variable given by *varName* as a list and appends each of the *value* arguments to that list as a separate element, with spaces between elements. If *varName* does not exist, it is created as a list with elements given by the *value* arguments. If *varName* indicate an element that does not exist of an array that has a default value set, list that is comprised of the default value with all the *value* arguments appended as elements will be stored in the array element. **Lappend** is similar to **append** except that the *value*s are appended as list elements rather than raw text. This command provides a relatively efficient way to build up large lists. For example, “**lappend a $b**” is much more efficient than “**set a \[concat $a \[list $b]]**” when **$a** is long.

# [EXAMPLE](#EXAMPLE)

Using **lappend** to build up a list of numbers.

```
% set var 1
1
% lappend var 2
1 2
% lappend var 3 4 5
1 2 3 4 5
```

# [SEE ALSO](#SEE_ALSO)

[list(n)](/man/os/tcl/list.n), [lassign(n)](/man/os/tcl/lassign.n), [ledit(n)](/man/os/tcl/ledit.n), [lindex(n)](/man/os/tcl/lindex.n), [linsert(n)](/man/os/tcl/linsert.n), [llength(n)](/man/os/tcl/llength.n), [lmap(n)](/man/os/tcl/lmap.n), [lpop(n)](/man/os/tcl/lpop.n), [lrange(n)](/man/os/tcl/lrange.n), [lremove(n)](/man/os/tcl/lremove.n), [lrepeat(n)](/man/os/tcl/lrepeat.n), [lreplace(n)](/man/os/tcl/lreplace.n), [lreverse(n)](/man/os/tcl/lreverse.n), [lsearch(n)](/man/os/tcl/lsearch.n), [lseq(n)](/man/os/tcl/lseq.n), [lset(n)](/man/os/tcl/lset.n), [lsort(n)](/man/os/tcl/lsort.n)

# [KEYWORDS](#KEYWORDS)

append, element, list, variable

Tcl

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Document: lappend(n) from tcl 9.1.0-r1 (Chainguard OS)
Source: https://downloads.sourceforge.net/project/tcl/Tcl/9.1.0/tcl9.1.0-src.tar.gz