Use dstringt::starts_with

[kroening]

• Each commit message has a non-empty body, explaining why the change was made.
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• Regression or unit tests are included, or existing tests cover the modified code (in this case I have detailed which ones those are in the commit message).
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[codecov]

Codecov Report

Attention: 18 lines in your changes are missing coverage. Please review.

Comparison is base (2d96b83) 79.68% compared to head (5747032) 79.68%.

Files	Patch %	Lines
src/goto-instrument/goto_program2code.cpp	42.85%	4 Missing ⚠️
src/goto-programs/show_goto_functions_xml.cpp	0.00%	4 Missing ⚠️
src/ansi-c/c_preprocess.cpp	33.33%	2 Missing ⚠️
src/goto-instrument/function.cpp	0.00%	2 Missing ⚠️
src/goto-instrument/race_check.cpp	0.00%	2 Missing ⚠️
src/goto-programs/graphml_witness.cpp	33.33%	2 Missing ⚠️
src/goto-instrument/branch.cpp	0.00%	1 Missing ⚠️
src/pointer-analysis/value_set_fi.cpp	83.33%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #8150      +/-   ##
===========================================
- Coverage    79.68%   79.68%   -0.01%     
===========================================
  Files         1681     1681              
  Lines       195296   195294       -2     
===========================================
- Hits        155624   155622       -2     
  Misses       39672    39672              

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[tautschnig]

This will break -DUSE_STD_STRING until we switch to c++20. Perhaps we should just document that USE_STD_STRING requires switching to that newer standard?

[kroening]

This will break -DUSE_STD_STRING until we switch to c++20. Perhaps we should just document that USE_STD_STRING requires switching to that newer standard?

I'd like to propose to get rid of it.

[tautschnig]

This will break -DUSE_STD_STRING until we switch to c++20. Perhaps we should just document that USE_STD_STRING requires switching to that newer standard?

I'd like to propose to get rid of it.

#8154, which I'd propose to merge first, and then rebase this one on top.

[tautschnig]

With #8154 merged this one should be good to go after a rebase.