topic Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro? in Python Questions

arcpy.AddMessage does not produce newlines in ArcGIS Pro?

GB_MattPanunto_GISS — Mon, 04 May 2020 06:19:51 GMT

I am working with ArcGIS Pro v2.4.1, and am trying to produce newlines using arcpy.AddMessage when running a script tool. I just want to create some blank spaces between messages, but none of the following seem to work when running the tool in ArcGIS Pro:

arcpy.AddMessage("\n")

arcpy.AddMessage("")

arcpy.AddMessage(" ")

However, these do work when running the tool in ArcMap. Is there a reason why these might not work in ArcGIS Pro?

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

FC_Basson — Fri, 10 Dec 2021 23:31:51 GMT

I think it is getting ignored or "trimmed".

I tested this code

import arcpy
arcpy.AddMessage("first line")
arcpy.AddMessage("\n ")
arcpy.AddMessage(".\n")
arcpy.AddMessage(".")
arcpy.AddMessage("second line")
arcpy.AddMessage("first line\nsecond line")‍‍‍‍‍‍‍‍‍‍‍‍‍

and got this output

So you might need to use an additional character to create a spacing between output lines.

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

JoshuaBixby — Mon, 04 May 2020 14:57:32 GMT

I see the same thing as FC Basson‌ with Pro 2.5. Personally, I would consider this a defect on Esri's part, but maybe they would consider it an 'enhancement' with Pro!

I tested a few white-space and control characters and all were getting stripped, but I did find that a zero-width space ('\u200B') works.

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

GB_MattPanunto_GISS — Mon, 04 May 2020 20:58:40 GMT

Good find! The '\u200B' seems to be working for me as well, but only for ArcGIS Pro, not ArcMap, ugh.

I guess inserting this line will provide a space in both environments:

arcpy.AddMessage("\u200B" if (sys.version_info[0] == 3) else "\n")

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

JoshuaBixby — Mon, 04 May 2020 21:32:37 GMT

To make it work in both ArcMap and Pro, just make it a Unicode literal:

arcpy.AddMessage(u"\u200B") ‍‍‍

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

GB_MattPanunto_GISS — Sat, 09 May 2020 02:56:13 GMT

Ahh yes, perfect!

Re: arcpy.AddMessage does not produce newlines in ArcGIS Pro?

MichaelVolz — Sat, 09 May 2020 17:02:17 GMT

Nice find Joshua!!!