[boost] debug_level=0 should emit -d0

[garethsb]

Specify library name and version: boost/all

• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
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[ghost]

I detected other pull requests that are modifying boost/all recipe:

• [boost] update usage of tools.apple_deployment_target_flag #4461
• [boost] visibility #4453
• add boost/1.65.1 #4354
• [boost] b2 user-config.jam needs CXX binary to be quoted as path may contain spaces #4149
• Boost/1.72.0/mpi #3959
• boost: patch serialization sources #3918

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[prince-chrismc]

based on the docs I think this would be fine too https://boostorg.github.io/build/manual/develop/index.html#bbv2.overview.invocation.options

-d0
Suppress all informational messages.
-d N
Enable cumulative debugging levels from 1 to n. Values are: +

It's unclear if a space is required

Suggested change

	if "debug_level" in self.options:
	command += " -d%d" % self.options.debug_level
	command += " -d%d" % self.options.get_safe("debug_level", 0)

[garethsb]

Thanks, @prince-chrismc.

For least surprise, should we default to the same value as b2 does itself, which I understand from that linked document to be level 1?

I'm pretty sure that the space is not required.

[prince-chrismc]

I picked the default for the recipe which was already accepted 🤷 we'll see what the CCI team and community say

[SSE4]

from my experience, space isn't required
using b2 default as recipe default matches the expectation for the most of users

[conan-center-bot]

All green in build 4 (e309342a372587f2d466d3ddb9a68b4b160d00f9)! 😊

• boost/1.69.0: Generated 131 packages. All logs here
• boost/1.70.0: Generated 131 packages. All logs here
• boost/1.71.0: Generated 131 packages. All logs here
• boost/1.72.0: Generated 131 packages. All logs here
• boost/1.73.0: Generated 131 packages. All logs here
• boost/1.74.0: Generated 131 packages. All logs here
• boost/1.75.0: Generated 131 packages. All logs here