context

Summary

The context statement reproduces part or all of the context buffer.

Syntax

... > context
... > context(offset)
... context(offset) > ...

Parameters

offset

The character offset in the context from which the output character is selected, starting at 1. The index increments for each character or statement found, with two caveats:

• outs() statements are expanded prior to calculating the offset.
• if() statements are not included in the calculation of the offset, which is different to how index() statements calculate offset.

This offset must be less than the offset of the context() statement itself, if the context() statement is in the context (third form above).

Description

The context statement reproduces the context stored from the rule match, or a single character of it, into the output. Use the context statement as much as possible as it is significantly faster than using the index statement.

A single character from the context can be output (on the right-hand side of a rule) or matched (on the left-hand side of a rule) using the context() form.

Note that although the context() form can be used in the left-hand side of a rule, the context form cannot.

Examples

Example: Using context

any(cons) "W" + any(key) > context index(keyout,3)
"contex" + "t" > context(2) context(6)     c outputs "ox"

Platforms

The context statement can be used in keyboards on all platforms.

Version history

The context(n) form was introduced in version 6.0.

The context statement was introduced in Keyman 3.0.

See also

• if() statement
• outs() statement