Try to evaluate an expressions and evaluate another expression on exception

Usage

try %except% except

Arguments

try: R expression
except: fallback R expression to be evaluated if try fails

Note

Suppress log messages in the except namespace if you don't want to throw a WARN log message on the exception branch.

Examples

everything %except% 42
#> WARN [2024-10-21 07:31:16] Running '42' as 'everything' failed: 'object 'everything' not found'
#> [1] 42
everything <- "640kb"
everything %except% 42
#> [1] "640kb"

FunDoesNotExist(1:10) %except% sum(1:10) / length(1:10)
#> WARN [2024-10-21 07:31:16] Running 'sum(1:10)' as 'FunDoesNotExist(1:10)' failed: 'could not find function "FunDoesNotExist"'
#> [1] 5.5
FunDoesNotExist(1:10) %except% (sum(1:10) / length(1:10))
#> WARN [2024-10-21 07:31:16] Running '(sum(1:10)/length(1:10))' as 'FunDoesNotExist(1:10)' failed: 'could not find function "FunDoesNotExist"'
#> [1] 5.5
FunDoesNotExist(1:10) %except% MEAN(1:10) %except% mean(1:10)
#> WARN [2024-10-21 07:31:16] Running 'MEAN(1:10)' as 'FunDoesNotExist(1:10)' failed: 'could not find function "FunDoesNotExist"'
#> WARN [2024-10-21 07:31:16] Running 'mean(1:10)' as 'FunDoesNotExist(1:10) %except% MEAN(1:10)' failed: 'could not find function "MEAN"'
#> [1] 5.5
FunDoesNotExist(1:10) %except% (MEAN(1:10) %except% mean(1:10))
#> WARN [2024-10-21 07:31:16] Running '(MEAN(1:10) %except% mean(1:10))' as 'FunDoesNotExist(1:10)' failed: 'could not find function "FunDoesNotExist"'
#> WARN [2024-10-21 07:31:16] Running 'mean(1:10)' as 'MEAN(1:10)' failed: 'could not find function "MEAN"'
#> [1] 5.5