script

A script is a sequence of commands, separated by a semicolon or newline, that an interpreter can evaluate. It is also usable as data format.

More generally, a script is a set of statements written in the language of an interpreter such as Tcl.

See Also

Dodekalogue

The rules of Tcl.

Many ways to eval

Enumerates the ways to evaluate a string as a script.

scriptSplit

Splits a script into its constituent commands.

parsetcl

scripted list

Performs substitutions on the words of each command in a script and then concatenates the commands into a single list.

Description

A script can be provided to Tcl in various ways:

Invocation of an interpreter such as tclsh

The name of a file containing the script can be passed as an argument.

source

The name of a file containing a script can be passed as an argument.

eval

Concatenates arguments into a script and evaluates it.

script substitution

A script is embedded into a command in a larger script.

A script often provides a library for use by other scripts.

Tcl's sparse syntax makes it particularly convenient to embed code written in another language directly into a Tcl script. SQL, Perl, ksh, awk, or even C code can then be handed off to to some other interpreter for evaluation. SQL is probably the most well-known example of this. When generating scripts for another language, it is necessary to be aware of possible injection attacks.