When you lint some code, Lint.jl will print the error messages in the format described below. Lint will return a LintResult which behaves like an iterable of LintMessages.



A message is of the following form:

filename.jl:Line CODE variable: message

filename.jl is the file that contains the problem.
Line is the line number relative to the start of the file.
CODE identifies the error and gives an indication of severity.
variable is the variable causing the error.
message is an explanation of the error.


There are 3 levels of severity a LintMessage can be:

  • Error: The most severe level. Will probably lead to program failure.
  • Warning: Code that will run but is probably wrong.
  • Info: Suggestions and best practices.

You can use iserror, iswarning and isinfo to check a particular messages error level.

If you only want to test for error and warning level messages you could use:

errors = filter(i -> !isinfo(i), lintpkg("MyPackage"))
@test isempty(errors)

Errors codes

Every error code starts with letter for the severity E:ERROR, W:WARN or I:INFO then has 3 numbers identifying the error. Below is a complete list of error codes:

code sample message
E1 Parsing Error
E100 expression not allowed in this context (the exact error message will be more specific about which expression is not allowed and where)
E101 this expression must be a T
E111 failed to parse
E112 incomplete expression
E121 Lint does not understand the expression
E131 Lint does not understand the argument #i
E132 lint does not understand the argument
E133 unknown keyword pattern
E134 unknown global pattern
E135 local declaration not understood by Lint
E136 (no longer used)
E137 lintpragma must be called using only string literals
E138 incomplete pragma expression
E139 (no longer used)
E140 (merged into E100)
E141 invalid macro syntax
E2 Miscellaneous Error
E211 deprecated message
E221 custum error
E3 Existence Error
E311 cannot find include file
E321 use of undeclared symbol
E331 duplicate argument
E332 should not be used as a variable name
E333 duplicate exports of symbol
E334 duplicate key in Dict
E4 Usage Error
E411 non-default argument following default arguments
E412 named ellipsis ... can only be the last argument
E413 positional ellipsis ... can only be the last argument
E414 (replaced by E100)
E415 (replaced by E100)
E416 (replaced by E100)
E417 anonymous function inside type definition
E418 RHS is a tuple, n of m variables used
E421 (no longer used)
E422 string uses * to concatenate
E423 named keyword argument must have a default
E424 (no longer used)
E425 use lintpragma macro inside type declaration
E431 use of length() in a Boolean context, use isempty()
E432 (no longer used)
E433 for a decreasing range, use a negative step e.g. 10:-1:1
E434 value at position #i is the referenced x. Possible typo?
E435 new is provided with more arguments than fields
E436 more indices than dimensions
E437 @compat called with wrong number of arguments
E5 Type Error
E511 apparent non-Bool type
E512 lint doesn't understand expresion in a boolean context
E513 leaf type as a type constraint it makes no sense
E516 type assertion and default seem inconsistent
E517 constructor-like function name doesn't match type T
E518 (merged into E522)
E519 (merged into E522)
E521 (merged into E522)
E522 indexing T with index types [S, U] is not supported
E523 (no longer used)
E524 (merged into E101)
E525 is of an immutable type
E531 multiple key types detected. Use Dict{Any,V}() for mixed type dict
E532 multiple value types detected. Use Dict{K,Any}() for mixed type dict
E533 type parameters are invariant, try f{T<:Number}(x::T)...
E534 introducing a new name for an implicit argument to the function, use {T<:X}
E535 (no longer used)
E536 use {T<:...} instead of a known type
E537 (removed)
E538 known type in parametric data type, use {T<:...}
E539 assigning an error to a variable
E6 Structure Error
E611 constructor doesn't seem to return the constructed object
W0 Linter Limitation
W100 this syntax not understood by Lint.jl
W101 unfortunately, Lint could not determine the exports of this module
W2 Miscellaneous Warning
W241 custom warning
W251 error; Symbol= X; rhstype= ...
W3 Existence Warning
W341 (merged into I340)
W351 (merged into I342)
W352 lambda argument conflicts with a local variable
W353 (merged into W352)
W354 lambda argument conflicts with an declared global
W355 conflicts with function name
W356 file included more than once
W357 including file that doesn't exist
W36 Import and Export Warning
W360 importing possibly undefined symbol
W361 exporting undefined symbol
W362 relative import has too many dots
W363 attempted import from probable non-module
W4 Usage Warning
W441 probably illegal use of inside curly
W443 did you forget an -> after @doc or make it inline?
W444 nested vcat is treated as a 1-dimensional array
W445 nested hcat is treated as a 1-row horizontal array of dim=2
W446 too many type parameters
W447 can't be #i type parameter for h; it should be of type t2
W448 an exception is instantiated but it is not being thrown
W449 this type is typically not constructible
W5 Type Warning
W541 (removed in Lint 0.3.0)
W542 comparing apparently incompatible types
W543 (no longer used)
W544 (no longer used)
W545 previously used variable has apparent type X, but now assigned Y
W546 implicitly discarding values, m of n used
W6 Structure Warning
W641 unreachable code after return
W642 true branch is unreachable
W643 false branch is unreachable
W644 redundant if-true statement
W645 while false block is unreachable
W651 the last of a expresion block looks different. Avg similarity score: X; Last part: Y
I1 Parsing Info
I171 LHS in assignment not understood by Lint
I2 Miscellaneous Info
I271 custom info
I281 (no longer used)
I3 Existence Info
I340 unused local variable
I341 local variable shadows global variable
I342 local variable shadows export from base
I343 global variable with same name as export from base
I344 local variable shadows other local variable
I371 use of undeclared symbol
I372 unable to follow non-literal include file
I381 unused lintpragma
I382 (merged into I340)
I391 (replaced with I341)
I392 (replaced with I341)
I393 using an existing type as type parameter name is probably a typo
I4 Usage Info
I472 assignment in the if-predicate clause
I473 value at position #i is the referenced y. OK if it represents permutations
I474 iteration generates tuples, n of m variables used
I475 bit-wise in a boolean context. (&,
I481 replace x() with y()
I482 used in a local scope. Improve readability by using 'local' or another name
I48[34567] (removed in Lint 0.3.0)
I5 Type Info
I571 the 1st statement under the true-branch is a boolean expression
I572 (removed)
I581 (removed in Lint 0.3.0)
I6 Structure Info
I671 new is provided with fewer arguments than fields
I672 iteration works for a number but it may be a typo
I681 ambiguity of :end as a symbol vs as part of a range
I682 ambiguity of [end -n] as a matrix row vs index [end-n]
I691 a type is not given to the field which can be slow
I692 array field has no dimension which can be slow
I7 Style Info
I771 type names should start with an upper case