Inserting 2 lines of text 2 lines prior to a known variable

Daniel James

I am working on modifying G-code file and I need to enter 2 lines of code 2 lines before a known value.
“M96” is the consistent value:
N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

I need to insert:
M107
FV.E. FEEDRATE[7]
2 Lines before every instance of “M96”
N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E.FEEDRATE[7]
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

I am able to add the text right above M96 by using the below, but I am not sure how to enter it 2 lines prior.

Find What = M96
Replace With = \n\M107\n\FV.E.FEEDRATE[7]\n\M96
Search Mode = REGULAR EXPRESSION
Dot Matches Newline =NOT CHECKED

PeterJones

@daniel-james ,

There are multiple ways of doing it.

One is to use a “lookahead” that matches two whole lines followed by a line containing M96. Because it’s a lookahead, the “cursor” is still at the beginning of the first of those three lines, so any replacement you do will be before those three lines, so 2 lines before the M96:
FIND = (?-s)(?=^.*$\R.*$\R.*M96\b)
REPLACE = M107\nFV.E.FEEDRATE[7]\n
SEARCH MODE = regular expression
(the (?-s) will cause the regex to be equivalent to .-matches-newline not checked whether or not it’s checked)
(Because the cursor was at the start of the line two lines before M96, I put the newlines at the end of each line in the replacement)

Note that I used the Unix LF \n for the newline in the replacement, which is what you showed (though I was confused by the extra \ between your \n and your M107 in the replacement). If you really have Windows CRLF newlines, use \r\n for each newline in the replacement.

You could also do a non-lookahead match which stores the previous two lines through the M96 in a capture group, or makes use of the $0 “whole capture” group:
FIND = (?-s)^.*$\R.*$\R.*M96\b
REPLACE = M107\nFV.E.FEEDRATE[7]\n$0
SEARCH MODE = Regular Expression

----

Useful References

Daniel James

@peterjones Thank you! I appreciate it!

guy038

Hello @daniel-James, @peterjones and All,

The regex S/R, provided by @peterjones, supposes that you click ONCE only on the Replace All button

Indeed, given this INPUT text :

N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

N153 G04 X50.0063 Y84.3353 I0.8597 J34.9894
N154 G05 X50.2137 Y85.8542 I-6.7013 J1.6885
N155 G870
N156 M96

Assuming that the Wrap around is ticked

And the following regex S/R :

SEARCH (?-si)(?=^.+\R.+\R.+M96\b)

REPLACE M107\nFV.E. FEEDRATE[7]\n

If you click, for instance, three times on the Replace All button, you’ll get the following OUTPUT text :

N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
M107
FV.E. FEEDRATE[7]
M107
FV.E. FEEDRATE[7]
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

N153 G04 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
M107
FV.E. FEEDRATE[7]
M107
FV.E. FEEDRATE[7]
N154 G05 X50.2137 Y85.8542 I-6.7013 J1.6885
N155 G870
N156 M96

Not exactly what we want, isn’t it ?

We can solve this problem by using backtracking control verbs. The idea is to use the couple (*SKIP)(*FAIL) or (*SKIP)(*F) with the generic regex :

What I DON’T want(*SKIP)(*F)|What I DO want

This leads to the practical regex S/R :

SEARCH (?-si)^M107\R(?:.+\R){3}.+M96\b(*SKIP)(*F)|(?=^.+\R.+\R.+M96\b)

REPLACE M107\nFV.E. FEEDRATE[7]\n

Note that the part to discard, before (*SKIP), is the five complete lines beginning with M107 and ending with M96

So, given the INPUT text, below, containing two sections where the two lines M107...FV.E... have already being inserted :

N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

N153 G05 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N154 G06 X50.2137 Y85.8542 I-6.7013 J1.6885
N155 G500
N156 M96

N157 G07 X50.0063 Y84.3353 I0.8597 J34.9894
N158 G08 X50.2137 Y85.8542 I-6.7013 J1.6885
N159 G100
N160 M96

N161 G00 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N162 G99 X50.2137 Y85.8542 I-6.7013 J1.6885
N163 G300
N164 M96

N165 G10 X50.0063 Y84.3353 I0.8597 J34.9894
N166 G20 X50.2137 Y85.8542 I-6.7013 J1.6885
N167 G000
N168 M96

The new regex S/R would give, after a first click on the Replace All button :

N149 G02 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N150 G03 X50.2137 Y85.8542 I-6.7013 J1.6885
N151 G260
N152 M96

N153 G05 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N154 G06 X50.2137 Y85.8542 I-6.7013 J1.6885
N155 G500
N156 M96

N157 G07 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N158 G08 X50.2137 Y85.8542 I-6.7013 J1.6885
N159 G100
N160 M96

N161 G00 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N162 G99 X50.2137 Y85.8542 I-6.7013 J1.6885
N163 G300
N164 M96

N165 G10 X50.0063 Y84.3353 I0.8597 J34.9894
M107
FV.E. FEEDRATE[7]
N166 G20 X50.2137 Y85.8542 I-6.7013 J1.6885
N167 G000
N168 M96

And, as expected, all the subsequent clicks, on the Replace All button, would return the message Replace All: O occurrences were replaced !

If we do not want to use the uncommon (*...) syntaxes, a solution, with a conditional replacement, could be :

SEARCH (?-si)(^M107\R(?:.+\R){3}.+M96\b)|(?=^.+\R.+\R.+M96\b)

REPLACE ?1$0:M107\nFV.E. FEEDRATE[7]\n

However, with this solution, and assuming our second INPUT text, we get :

Five replacements after a first click on the Replace All button ( Two identical replacements and three insertions )
Five identical replacements after any subsequent click on the Replace All button

Best Regards,

guy038

Alan Kilborn

@guy038 said in Inserting 2 lines of text 2 lines prior to a known variable:

What I DON’T want(*SKIP)(*F)|What I DO want

THAT is a nice way to put it. :-)

guy038

Hi, @alan-kilborn, and All,

Actually, I was inspired by this article :

https://www.rexegg.com/backtracking-control-verbs.html#skipfail

where it is said :

In effect, (*SKIP)(*FAIL) says: “Throw away anything you can match to the left of me.”

Please, visit this excellent regex site :

https://www.rexegg.com

BR

guy038