I was quite surprised to see the following in REPL:
julia> macro g(ex)
"Some value"
end
@g (macro with 1 method)
julia> @g 1
"Some value"
julia> @g 1;
julia> @g 1 # comment
"Some value"
julia> @g 1; # comment
julia> @g 1; # comment;
julia> @g 1; # comment; another comment
"Some value"
julia> @g 1; # comment; another comment;
julia> @g(1); # comment
julia> @g(1); # comment; another comment
"Some value"
julia> @g(1); # comment; another comment;
julia> @g(1) # comment
"Some value"
julia> @g(1) # comment;
julia>
It means that the behavior of REPL is sensitive to the fact if we used ; in a comment or not (and the expectation is that after # all text should be ignored unless).
This is not a purely artificial question. A common case when this might happen is when we use @time or @btime and log benchmark results. If you also have comments in the line that contains macro the benchmark results volume can unexpectedly explode. Here is a simple example:
julia> @time rand(1000, 1000); # all OK
0.028492 seconds (5.33 k allocations: 7.906 MiB)
julia> @time rand(1000, 1000); # all OK; but now it is not
0.002986 seconds (6 allocations: 7.630 MiB)
1000×1000 Array{Float64,2}:
0.0267641 0.658582 0.848755 0.317831 0.688003 0.358419 0.451134 0.23211 0.959732 … 0.900364 0.510592 0.548442 0.278663 0.62676 0.637126 0.230665 0.21124
0.573036 0.343188 0.826076 0.730182 0.136591 0.195317 0.493071 0.949521 0.423192 0.305033 0.876593 0.244199 0.386221 0.969509 0.319844 0.335223 0.829834
0.856271 0.400261 0.698654 0.841522 0.625836 0.860484 0.200021 0.0116017 0.0875489 0.0179683 0.0320464 0.63124 0.00268192 0.873807 0.839423 0.635909 0.555291
0.852382 0.960672 0.153343 0.293958 0.15946 0.820972 0.784847 0.390328 0.469626 0.776801 0.397079 0.80543 0.275 0.14089 0.47268 0.0156535 0.85925
0.25104 0.20491 0.428919 0.857973 0.753786 0.0301861 0.395199 0.369403 0.47481 0.047398 0.799893 0.652982 0.696275 0.492488 0.448998 0.0513526 0.338989
0.393509 0.607272 0.334652 0.46158 0.274222 0.804766 0.970835 0.71435 0.359019 … 0.864391 0.438048 0.808643 0.721354 0.688137 0.465822 0.00739675 0.824901
0.889251 0.703329 0.759935 0.709762 0.565584 0.628499 0.00271273 0.51494 0.897257 0.161289 0.641785 0.56721 0.594981 0.822345 0.166982 0.0249376 0.892944
0.709555 0.411339 0.996607 0.731638 0.590527 0.435896 0.232339 0.666103 0.490926 0.072736 0.770996 0.647315 0.392009 0.616822 0.404794 0.712745 0.735653
0.862593 0.402576 0.692238 0.524676 0.585742 0.138828 0.66776 0.418467 0.818053 0.395829 0.303623 0.363488 0.813408 0.125701 0.494382 0.455527 0.478308
0.872455 0.920469 0.392234 0.29627 0.165056 0.151531 0.428493 0.225258 0.72585 0.464203 0.674847 0.976506 0.487631 0.676531 0.0794573 0.9357 0.771471
0.157901 0.25171 0.35577 0.987172 0.386309 0.049215 0.222573 0.294111 0.761429 … 0.141349 0.234049 0.76048 0.547256 0.167864 0.711885 0.152854 0.658445
0.589158 0.0245295 0.918736 0.581051 0.142954 0.972766 0.53413 0.140499 0.294059 0.0350834 0.563872 0.724622 0.982327 0.490663 0.672911 0.803811 0.337851
0.423949 0.0140113 0.415359 0.120011 0.612815 0.383749 0.341847 0.297124 0.755884 0.517018 0.105703 0.928132 0.692935 0.711834 0.980814 0.178398 0.145736
0.0600562 0.560431 0.0226274 0.793114 0.815692 0.599694 0.284682 0.675083 0.605591 0.0634941 0.716539 0.877788 0.699433 0.670576 0.257364 0.715528 0.72092
0.424772 0.443975 0.0783245 0.32872 0.436885 0.864198 0.0958389 0.527964 0.122099 0.2896 0.854291 0.286997 0.869232 0.0159727 0.970274 0.757292 0.709655
0.137642 0.552306 0.340412 0.870594 0.8005 0.58662 0.704773 0.205258 0.929446 … 0.149419 0.889036 0.750801 0.832122 0.158465 0.524737 0.836708 0.856735
0.934958 0.775266 0.193415 0.139921 0.77649 0.091841 0.442313 0.379873 0.210962 0.561086 0.340543 0.573748 0.252492 0.41789 0.756878 0.475725 0.619045
0.638356 0.736071 0.195017 0.686435 0.297163 0.826745 0.292213 0.676927 0.332895 0.157774 0.296899 0.565132 0.142281 0.268541 0.997655 0.262132 0.0477603
0.16549 0.359255 0.1783 0.3693 0.0963325 0.841711 0.996923 0.297843 0.267039 0.863845 0.40365 0.917608 0.653329 0.825724 0.316271 0.88585 0.717097
0.532575 0.38428 0.846096 0.303175 0.36408 0.626931 0.915248 0.782076 0.831681 0.827864 0.168862 0.313873 0.966666 0.755359 0.519957 0.512541 0.199088
0.0359976 0.064213 0.491815 0.613698 0.346771 0.794803 0.451207 0.613652 0.862894 … 0.82131 0.484946 0.44644 0.0967432 0.273457 0.03746 0.665998 0.138288
0.68198 0.0610806 0.675673 0.972068 0.10548 0.828372 0.342581 0.180128 0.644963 0.249285 0.180819 0.792028 0.340836 0.892033 0.295675 0.0940658 0.267208
0.668541 0.401939 0.79358 0.746644 0.927863 0.0135706 0.394751 0.727533 0.113493 0.345811 0.314602 0.0864143 0.953271 0.236522 0.258167 0.909776 0.925962
0.0922822 0.884553 0.774214 0.458847 0.756019 0.500089 0.678584 0.192439 0.631339 0.096009 0.310327 0.393652 0.538764 0.930267 0.757297 0.779954 0.244525
0.454251 0.0322761 0.465341 0.895469 0.0625092 0.532418 0.583566 0.821984 0.896099 0.48433 0.843093 0.526709 0.61162 0.847836 0.1635 0.392544 0.918549
⋮ ⋮ ⋱ ⋮
0.727286 0.106576 0.763713 0.986037 0.167134 0.434408 0.885278 0.234356 0.659182 0.40644 0.0681324 0.815116 0.648259 0.674225 0.995851 0.948789 0.808887
0.38977 0.943557 0.19886 0.617703 0.159148 0.412448 0.219963 0.805158 0.588202 0.196682 0.072714 0.426219 0.381959 0.663514 0.466398 0.0162166 0.802478
0.116801 0.742059 0.401393 0.528056 0.0541768 0.256147 0.927635 0.719834 0.525814 0.592159 0.523849 0.571465 0.0326836 0.306318 0.839485 0.183633 0.0165282
0.718953 0.547046 0.821147 0.18311 0.915053 0.483597 0.10538 0.517791 0.749066 0.928134 0.284119 0.425519 0.390993 0.85582 0.0638284 0.775352 0.754087
0.71819 0.809737 0.0654892 0.913811 0.757074 0.164386 0.528953 0.994725 0.858255 … 0.846287 0.179156 0.687095 0.563957 0.511393 0.596384 0.583887 0.841501
0.585481 0.416224 0.934921 0.929297 0.303899 0.897434 0.240078 0.782317 0.910373 0.621187 0.703555 0.0383639 0.204674 0.975596 0.900892 0.767434 0.363289
0.39524 0.131929 0.992866 0.068157 0.507883 0.654878 0.610657 0.577879 0.00957053 0.345147 0.226008 0.338321 0.935626 0.60693 0.859111 0.383681 0.316735
0.480617 0.0918676 0.18141 0.909645 0.608337 0.670476 0.682836 0.824339 0.805192 0.499084 0.661822 0.351314 0.60607 0.461762 0.381912 0.553977 0.871948
0.787662 0.591027 0.472551 0.222001 0.0655733 0.116074 0.724356 0.972063 0.512234 0.677201 0.89766 0.273225 0.268796 0.571354 0.291354 0.304498 0.503353
0.0627622 0.505999 0.912835 0.888306 0.58696 0.446313 0.927461 0.0156876 0.408947 … 0.740654 0.638439 0.680929 0.364069 0.791384 0.190683 0.596154 0.429361
0.948272 0.397318 0.408595 0.589306 0.524703 0.844776 0.735696 0.218957 0.963029 0.635286 0.218833 0.952485 0.263801 0.0543318 0.769076 0.109304 0.722779
0.27112 0.975753 0.520775 0.495836 0.920183 0.651118 0.334148 0.401216 0.270204 0.905123 0.752772 0.278488 0.648417 0.268399 0.097165 0.314593 0.634961
0.767498 0.14352 0.0404379 0.617141 0.679762 0.83504 0.945535 0.620964 0.997305 0.633123 0.347835 0.0712735 0.532536 0.579622 0.247206 0.563325 0.698014
0.482833 0.711086 0.0395703 0.896233 0.296759 0.906968 0.325958 0.380955 0.548374 0.605732 0.296735 0.00830663 0.215665 0.693552 0.699519 0.700885 0.939767
0.789204 0.858355 0.237738 0.388806 0.414321 0.42554 0.713096 0.960728 0.8659 … 0.33489 0.100444 0.26247 0.910938 0.273536 0.686318 0.259117 0.486116
0.880129 0.640954 0.975515 0.864191 0.0699951 0.0465749 0.383876 0.255432 0.592298 0.161853 0.427513 0.45963 0.342952 0.999757 0.0772689 0.255583 0.313283
0.600257 0.380218 0.169106 0.449569 0.754442 0.896011 0.623048 0.649595 0.275728 0.628487 0.907642 0.0955009 0.178071 0.142105 0.456238 0.782727 0.613741
0.611542 0.380539 0.821424 0.441122 0.0553052 0.332895 0.477381 0.479204 0.422758 0.489139 0.0348038 0.26374 0.138535 0.972803 0.74023 0.666659 0.457319
0.366427 0.597743 0.408222 0.543907 0.812792 0.218637 0.80632 0.160942 0.694943 0.36444 0.276327 0.977391 0.786791 0.356966 0.492407 0.712287 0.861778
0.70826 0.739991 0.0771072 0.851083 0.777034 0.943255 0.566574 0.323754 0.253069 … 0.363804 0.695912 0.0336533 0.518607 0.101784 0.0545115 0.351019 0.663125
0.985455 0.551387 0.364168 0.932284 0.0588912 0.462793 0.289022 0.744923 0.486689 0.381584 0.621326 0.363666 0.203018 0.382784 0.74265 0.265523 0.620865
0.863684 0.907237 0.48292 0.453384 0.692192 0.148738 0.258507 0.769743 0.769718 0.386317 0.0224697 0.139299 0.173425 0.102454 0.636354 0.686261 0.568425
0.41339 0.556762 0.778314 0.494947 0.01019 0.181109 0.741261 0.662134 0.985842 0.323563 0.440997 0.414983 0.945543 0.732891 0.407309 0.298331 0.594593
0.209233 0.502239 0.442412 0.831158 0.540056 0.532196 0.0342574 0.435019 0.83454 0.799601 0.791672 0.483698 0.011429 0.760036 0.163032 0.309858 0.945666
julia>