deprecate 2-argument assert function

this is a performance trap since it can lead to unconditionally constructing a message string on every call

base/deprecated.jl

@@ -134,6 +134,7 @@ export PipeString
 @deprecate min(f::Function,x)  minimum(f,x)
 @deprecate max(x,_::(),d)      maximum(x,d)
 @deprecate min(x,_::(),d)      minimum(x,d)
+@deprecate assert(x,y)         (@assert x y)
 
 deprecated_ls() = run(`ls -l`)
 deprecated_ls(args::Cmd) = run(`ls -l $args`)

base/error.jl

@@ -39,10 +39,10 @@ systemerror(p, b::Bool) = b ? throw(SystemError(string(p))) : nothing
 
 ## assertion functions and macros ##
 
-assert(x) = assert(x,'?')
-assert(x,labl) = x ? nothing : error("assertion failed: ", labl)
-macro assert(ex)
-    :($(esc(ex)) ? nothing : error("assertion failed: ", string($(Expr(:quote,ex)))))
+assert(x) = x ? nothing : error("assertion failed")
+macro assert(ex,msg...)
+    msg = isempty(msg) ? :(string($(Expr(:quote,ex)))) : esc(msg[1])
+    :($(esc(ex)) ? nothing : error("assertion failed: ", $msg))
 end
 
 ## printing with color ##

base/inference.jl

@@ -955,7 +955,7 @@ function abstract_interpret(e::Expr, vtypes, sv::StaticVarInfo)
         if isa(lhs,SymbolNode)
             lhs = lhs.name
         end
-        assert(isa(lhs,Symbol), "inference.jl:579")
+        assert(isa(lhs,Symbol))
         return StateUpdate(lhs, t, vtypes)
     elseif is(e.head,:call) || is(e.head,:call1)
         abstract_eval(e, vtypes, sv)
@@ -1168,7 +1168,7 @@ function typeinf(linfo::LambdaStaticData,atypes::Tuple,sparams::Tuple, def, cop)
 
     args = f_argnames(ast)
     la = length(args)
-    assert(is(ast.head,:lambda), "inference.jl:745")
+    assert(is(ast.head,:lambda))
     locals = (ast.args[2][1])::Array{Any,1}
     vars = [args, locals]
     body = (ast.args[3].args)::Array{Any,1}
@@ -1836,8 +1836,8 @@ function inlineable(f, e::Expr, sv, enclosing_ast)
     if length(body) != 1
         return NF
     end
-    assert(isa(body[1],Expr), "inference.jl:1050")
-    assert(is(body[1].head,:return), "inference.jl:1051")
+    assert(isa(body[1],Expr))
+    assert(is(body[1].head,:return))
     # check for vararg function
     args = f_argnames(ast)
     expr = body[1].args[1]

base/stream.jl

@@ -608,7 +608,7 @@ function readall(stream::AsyncStream)
 end
 
 function read{T}(this::AsyncStream, a::Array{T})
-    assert(isbits(T),"Read from Buffer only supports bits types or arrays of bits types")
+    isbits(T) || error("Read from Buffer only supports bits types or arrays of bits types")
     nb = length(a)*sizeof(T)
     buf = this.buffer
     @assert buf.seekable == false