ed: search forward starting from next line

[mknos]

• Problem1: If a search failed, ed was incorrectly raising Invalid Address error
• We want to agree with GNU ed, and raise a No Match error in this case
• The abstraction is kind of broken because sub-commands are usually called after edParse() returns
• In the case of edSearchForward() and edSearchBackward(), it is called by edParse()->edCalculateLine()
• Designate CalculateLine() return value -1 as match error, and teach edParse() to handle this
• Test1: search for non-existent pattern in script "awk": "?sdfsklfjhsdffd" and "/sd234234234"
• Future work: move search code out of CalculateLine()?
• Problem2: edSearchForwards() is supposed to start searching from currentLine+1, not currentLine (found when testing against GNU ed)
• Test2: Jump to line 1 of script "awk" then search forwards for pattern "perl"

perl ed -p '>>> ' awk
4595
>>> 1
#!/usr/bin/perl
>>> /perl
Author: Tom Christiansen, tchrist@perl.com
>>> n
7	Author: Tom Christiansen, tchrist@perl.com
>>> q