Skip to content

5.2 lou_trace

When working on translation tables it is sometimes useful to determine what rules were applied when translating a string. lou_trace helps with exactly that. It list all the the applied rules for a given translation table and an input string.

lou_trace [OPTIONS] TABLE[,TABLE,...]

Aside from the standard options (see common options) lou_trace also accepts the following options:

--forward
-f

Trace a forward translation.

--backward
-b

Trace a backward translation.

If no options are given forward translation is assumed.

Once started you can type an input string followed by RET. lou_trace will print the braille translation followed by list of rules that were applied to produce the translation. A possible invocation is listed in the following example:

$ lou_trace tables/en-us-g2.ctb 
the u.s. postal service
! u4s4 po/al s}vice
1.      largesign       the     2346
2.      repeated                0
3.      lowercase       u       136
4.      punctuation     .       46
5.      context _$l["."]$l      @256
6.      lowercase       s       234
7.      postpunc        .       256
8.      repeated                0
9.      begword post    1234-135-34
10.     largesign       a       1
11.     lowercase       l       123
12.     repeated                0
13.     lowercase       s       234
14.     always  er      12456
15.     lowercase       v       1236
16.     lowercase       i       24
17.     lowercase       c       14
18.     lowercase       e       15
19.     pass2   $s1-10  @0
20.     pass2   $s1-10  @0
21.     pass2   $s1-10  @0