Create AbstractStructuredExpression

[MilesCranmer]

This modifies StructuredExpression to subtype an abstract class. This is so that SymbolicRegression.jl can introduce a new expression type that permits providing constraints.

[coveralls]

Pull Request Test Coverage Report for Build 11316658232

Details

• 21 of 21 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.008%) to 95.365%

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Totals
Change from base Build 11301554059:	0.008%
Covered Lines:	2407
Relevant Lines:	2524

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💛 - Coveralls

[github-actions]

Benchmark Results

	master	818e7d2...	master/818e7d25b7d05c...
eval/ComplexF32/evaluation	7.26 ± 0.6 ms	7.21 ± 0.57 ms	1.01
eval/ComplexF64/evaluation	10.7 ± 0.98 ms	10.7 ± 0.86 ms	1
eval/Float32/derivative	11.7 ± 1.1 ms	11.7 ± 1.2 ms	0.999
eval/Float32/derivative_turbo	11.8 ± 1.3 ms	11.7 ± 1.2 ms	1.01
eval/Float32/evaluation	2.74 ± 0.25 ms	2.71 ± 0.24 ms	1.01
eval/Float32/evaluation_bumper	0.575 ± 0.015 ms	0.607 ± 0.014 ms	0.947
eval/Float32/evaluation_turbo	0.575 ± 0.034 ms	0.568 ± 0.034 ms	1.01
eval/Float32/evaluation_turbo_bumper	0.577 ± 0.014 ms	0.606 ± 0.014 ms	0.952
eval/Float64/derivative	15.3 ± 0.83 ms	15.5 ± 0.81 ms	0.99
eval/Float64/derivative_turbo	15.2 ± 0.86 ms	15.2 ± 0.92 ms	0.998
eval/Float64/evaluation	3.24 ± 0.32 ms	3.16 ± 0.31 ms	1.03
eval/Float64/evaluation_bumper	1.19 ± 0.045 ms	1.25 ± 0.043 ms	0.951
eval/Float64/evaluation_turbo	1.06 ± 0.07 ms	1.06 ± 0.069 ms	1
eval/Float64/evaluation_turbo_bumper	1.2 ± 0.045 ms	1.26 ± 0.046 ms	0.953
utils/combine_operators/break_sharing	0.0388 ± 0.0012 ms	0.0385 ± 0.0005 ms	1.01
utils/convert/break_sharing	27.8 ± 2.7 μs	27.5 ± 2.4 μs	1.01
utils/convert/preserve_sharing	0.0991 ± 0.0044 ms	0.099 ± 0.0038 ms	1
utils/copy/break_sharing	28.9 ± 2.5 μs	28.1 ± 2.1 μs	1.03
utils/copy/preserve_sharing	0.1 ± 0.0037 ms	0.0996 ± 0.0039 ms	1.01
utils/count_constant_nodes/break_sharing	8.42 ± 0.21 μs	8.86 ± 0.27 μs	0.951
utils/count_constant_nodes/preserve_sharing	0.0867 ± 0.0038 ms	0.0883 ± 0.0033 ms	0.983
utils/count_depth/break_sharing	9.8 ± 0.24 μs	9.66 ± 0.2 μs	1.02
utils/count_nodes/break_sharing	8.35 ± 0.22 μs	8.41 ± 0.17 μs	0.993
utils/count_nodes/preserve_sharing	0.0853 ± 0.0038 ms	0.0863 ± 0.0028 ms	0.988
utils/get_set_constants!/break_sharing	0.0348 ± 0.0026 ms	0.033 ± 0.0021 ms	1.05
utils/get_set_constants!/preserve_sharing	0.177 ± 0.0065 ms	0.178 ± 0.0056 ms	0.997
utils/get_set_constants_parametric	0.045 ± 0.0024 ms	0.0458 ± 0.0022 ms	0.982
utils/has_constants/break_sharing	4.28 ± 0.18 μs	4.12 ± 0.13 μs	1.04
utils/has_operators/break_sharing	2.26 ± 0.094 μs	2.02 ± 0.08 μs	1.12
utils/hash/break_sharing	22.8 ± 0.56 μs	22.7 ± 0.64 μs	1
utils/hash/preserve_sharing	0.0979 ± 0.0038 ms	0.0982 ± 0.0034 ms	0.996
utils/index_constant_nodes/break_sharing	26.3 ± 0.88 μs	26.2 ± 1.2 μs	1.01
utils/index_constant_nodes/preserve_sharing	0.0995 ± 0.0037 ms	0.0987 ± 0.0034 ms	1.01
utils/is_constant/break_sharing	4.06 ± 0.13 μs	4.45 ± 0.11 μs	0.911
utils/simplify_tree/break_sharing	0.176 ± 0.0029 ms	0.182 ± 0.0088 ms	0.971
utils/simplify_tree/preserve_sharing	0.226 ± 0.0059 ms	0.225 ± 0.0056 ms	1
utils/string_tree/break_sharing	0.476 ± 0.019 ms	0.474 ± 0.016 ms	1
utils/string_tree/preserve_sharing	0.582 ± 0.02 ms	0.581 ± 0.021 ms	1
time_to_load	0.206 ± 0.002 s	0.207 ± 0.0012 s	0.998