vim-patch:8.1.1879: more functions can be used as methods

Problem:    More functions can be used as methods.
Solution:   Make float functions usable as a method.
https://github.com/vim/vim/commit/93cf85f9ef02931de3f8c8e536a137da0b48b7dc

Fix atan2() doc typo (patch referred to it as atan()).
Adjust Test_fmod() method test to expect "str2float('nan')".

3 files changed, 122 insertions, 27 deletions

diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index e180836917..814931ff2b 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1060,7 +1060,14 @@ next method: >
 <
 Example of using a lambda: >
 	GetPercentage->{x -> x * 100}()->printf('%d%%')
-
+<
+When using -> the |expr7| operators will be applied first, thus: >
+	-1.234->string()
+Is equivalent to: >
+	(-1.234)->string()
+And NOT: >
+	-(1.234->string())
+<
 							*E274*
 "->name(" must not contain white space.  There can be white space before the
 "->" and after the "(", thus you can split the lines like this: >
@@ -2609,6 +2616,8 @@ abs({expr})							*abs()*
 			echo abs(-4)
 <			4
 
+		Can also be used as a |method|: >
+			Compute()->abs()
 
 acos({expr})							*acos()*
 		Return the arc cosine of {expr} measured in radians, as a
@@ -2621,6 +2630,8 @@ acos({expr})							*acos()*
 			:echo acos(-0.5)
 <			2.094395
 
+		Can also be used as a |method|: >
+			Compute()->acos()
 
 add({list}, {expr})					*add()*
 		Append the item {expr} to |List| {list}.  Returns the
@@ -2630,10 +2641,10 @@ add({list}, {expr})					*add()*
 <		Note that when {expr} is a |List| it is appended as a single
 		item.  Use |extend()| to concatenate |Lists|.
 		Use |insert()| to add an item at another position.
+
 		Can also be used as a |method|: >
 			mylist->add(val1)->add(val2)
 
-
 and({expr}, {expr})					*and()*
 		Bitwise AND on the two arguments.  The arguments are converted
 		to a number.  A List, Dict or Float argument causes an error.
@@ -2735,6 +2746,9 @@ asin({expr})						*asin()*
 			:echo asin(-0.5)
 <			-0.523599
 
+		Can also be used as a |method|: >
+			Compute()->asin()
+
 
 assert_ functions are documented here: |assert-functions-details|
 
@@ -2749,6 +2763,8 @@ atan({expr})						*atan()*
 			:echo atan(-4.01)
 <			-1.326405
 
+		Can also be used as a |method|: >
+			Compute()->atan()
 
 atan2({expr1}, {expr2})					*atan2()*
 		Return the arc tangent of {expr1} / {expr2}, measured in
@@ -2760,6 +2776,8 @@ atan2({expr1}, {expr2})					*atan2()*
 			:echo atan2(1, -1)
 <			2.356194
 
+		Can also be used as a |method|: >
+			Compute()->atan2(1)
 
 							*browse()*
 browse({save}, {title}, {initdir}, {default})
@@ -2966,6 +2984,9 @@ ceil({expr})							*ceil()*
 			echo ceil(4.0)
 <			4.0
 
+		Can also be used as a |method|: >
+			Compute()->ceil()
+
 changenr()						*changenr()*
 		Return the number of the most recent change.  This is the same
 		number as what is displayed with |:undolist| and can be used
@@ -3261,6 +3282,8 @@ cos({expr})						*cos()*
 			:echo cos(-4.01)
 <			-0.646043
 
+		Can also be used as a |method|: >
+			Compute()->cos()
 
 cosh({expr})						*cosh()*
 		Return the hyperbolic cosine of {expr} as a |Float| in the range
@@ -3272,6 +3295,8 @@ cosh({expr})						*cosh()*
 			:echo cosh(-0.5)
 <			-1.127626
 
+		Can also be used as a |method|: >
+			Compute()->cosh()
 
 count({comp}, {expr} [, {ic} [, {start}]])			*count()*
 		Return the number of times an item with value {expr} appears
@@ -3704,6 +3729,9 @@ exp({expr})						*exp()*
 			:echo exp(-1)
 <			0.367879
 
+		Can also be used as a |method|: >
+			Compute()->exp()
+
 debugbreak({pid})					*debugbreak()*
 		Specifically used to interrupt a program being debugged.  It
 		will cause process {pid} to get a SIGTRAP.  Behavior for other
@@ -4017,6 +4045,8 @@ float2nr({expr})					*float2nr()*
 			echo float2nr(1.0e-100)
 <			0
 
+		Can also be used as a |method|: >
+			Compute()->float2nr()
 
 floor({expr})							*floor()*
 		Return the largest integral value less than or equal to
@@ -4030,6 +4060,8 @@ floor({expr})							*floor()*
 			echo floor(4.0)
 <			4.0
 
+		Can also be used as a |method|: >
+			Compute()->floor()
 
 fmod({expr1}, {expr2})					*fmod()*
 		Return the remainder of {expr1} / {expr2}, even if the
@@ -4045,6 +4077,8 @@ fmod({expr1}, {expr2})					*fmod()*
 			:echo fmod(-12.33, 1.22)
 <			-0.13
 
+		Can also be used as a |method|: >
+			Compute()->fmod(1.22)
 
 fnameescape({string})					*fnameescape()*
 		Escape {string} for use as file name command argument.  All
@@ -5605,6 +5639,9 @@ isinf({expr})						*isinf()*
 			:echo isinf(-1.0 / 0.0)
 <			-1
 
+		Can also be used as a |method|: >
+			Compute()->isinf()
+
 islocked({expr})					*islocked()* *E786*
 		The result is a Number, which is |TRUE| when {expr} is the
 		name of a locked variable.
@@ -5648,6 +5685,9 @@ isnan({expr})						*isnan()*
 			echo isnan(0.0 / 0.0)
 <			1
 
+		Can also be used as a |method|: >
+			Compute()->isnan()
+
 jobpid({job})						*jobpid()*
 		Return the PID (process id) of |job-id| {job}.
 
@@ -5950,6 +5990,8 @@ log({expr})						*log()*
 			:echo log(exp(5))
 <			5.0
 
+		Can also be used as a |method|: >
+			Compute()->log()
 
 log10({expr})						*log10()*
 		Return the logarithm of Float {expr} to base 10 as a |Float|.
@@ -5960,6 +6002,9 @@ log10({expr})						*log10()*
 			:echo log10(0.01)
 <			-2.0
 
+		Can also be used as a |method|: >
+			Compute()->log10()
+
 luaeval({expr}[, {expr}])
 		Evaluate Lua expression {expr} and return its result converted
 		to Vim data structures. See |lua-eval| for more details.
@@ -6637,6 +6682,9 @@ pow({x}, {y})						*pow()*
 			:echo pow(32, 0.20)
 <			2.0
 
+		Can also be used as a |method|: >
+			Compute()->pow(3)
+
 prevnonblank({lnum})					*prevnonblank()*
 		Return the line number of the first line at or above {lnum}
 		that is not blank.  Example: >
@@ -7234,6 +7282,9 @@ round({expr})							*round()*
 			echo round(-4.5)
 <			-5.0
 
+		Can also be used as a |method|: >
+			Compute()->round()
+
 rpcnotify({channel}, {event}[, {args}...])			*rpcnotify()*
 		Sends {event} to {channel} via |RPC| and returns immediately.
 		If {channel} is 0, the event is broadcast to all channels.
@@ -8210,6 +8261,8 @@ sin({expr})						*sin()*
 			:echo sin(-4.01)
 <			0.763301
 
+		Can also be used as a |method|: >
+			Compute()->sin()
 
 sinh({expr})						*sinh()*
 		Return the hyperbolic sine of {expr} as a |Float| in the range
@@ -8221,6 +8274,9 @@ sinh({expr})						*sinh()*
 			:echo sinh(-0.9)
 <			-1.026517
 
+		Can also be used as a |method|: >
+			Compute()->sinh()
+
 sockconnect({mode}, {address}, {opts})			 *sockconnect()*
 		Connect a socket to an address. If {mode} is "pipe" then
 		{address} should be the path of a named pipe. If {mode} is
@@ -8410,6 +8466,8 @@ sqrt({expr})						*sqrt()*
 <			nan
 		"nan" may be different, it depends on system libraries.
 
+		Can also be used as a |method|: >
+			Compute()->sqrt()
 
 stdioopen({opts})			 *stdioopen()*
 		With |--headless| this opens stdin and stdout as a |channel|.
@@ -8461,6 +8519,9 @@ str2float({expr})					*str2float()*
 		12.0.  You can strip out thousands separators with
 		|substitute()|: >
 			let f = str2float(substitute(text, ',', '', 'g'))
+<
+		Can also be used as a |method|: >
+			let f = text->substitute(',', '', 'g')->str2float()
 
 str2list({expr} [, {utf8}])				*str2list()*
 		Return a list containing the number values which represent
@@ -9112,6 +9173,8 @@ tan({expr})						*tan()*
 			:echo tan(-4.01)
 <			-1.181502
 
+		Can also be used as a |method|: >
+			Compute()->tan()
 
 tanh({expr})						*tanh()*
 		Return the hyperbolic tangent of {expr} as a |Float| in the
@@ -9123,6 +9186,8 @@ tanh({expr})						*tanh()*
 			:echo tanh(-1)
 <			-0.761594
 
+		Can also be used as a |method|: >
+			Compute()->tanh()
 
 							*timer_info()*
 timer_info([{id}])
@@ -9249,6 +9314,9 @@ trunc({expr})							*trunc()*
 			echo trunc(4.0)
 <			4.0
 
+		Can also be used as a |method|: >
+			Compute()->trunc()
+
 type({expr})							*type()*
 		The result is a Number representing the type of {expr}.
 		Instead of using the number directly, it is better to use the
diff --git a/src/nvim/eval.lua b/src/nvim/eval.lua
index a629fd9889..1cac57a8ff 100644
--- a/src/nvim/eval.lua
+++ b/src/nvim/eval.lua
@@ -21,8 +21,8 @@ local LAST = "BASE_LAST"
 
 return {
   funcs={
-    abs={args=1},
-    acos={args=1, func="float_op_wrapper", data="&acos"},  -- WJMc
+    abs={args=1, base=1},
+    acos={args=1, base=1, func="float_op_wrapper", data="&acos"},  -- WJMc
     add={args=2, base=1},
     ['and']={args=2},
     api_info={},
@@ -32,7 +32,7 @@ return {
     argidx={},
     arglistid={args={0, 2}},
     argv={args={0, 2}},
-    asin={args=1, func="float_op_wrapper", data="&asin"},  -- WJMc
+    asin={args=1, base=1, func="float_op_wrapper", data="&asin"},  -- WJMc
     assert_beeps={args={1}, base=1},
     assert_equal={args={2, 3}, base=2},
     assert_equalfile={args={2, 3}},
@@ -46,8 +46,8 @@ return {
     assert_notmatch={args={2, 3}, base=2},
     assert_report={args=1},
     assert_true={args={1, 2}, base=1},
-    atan={args=1, func="float_op_wrapper", data="&atan"},
-    atan2={args=2},
+    atan={args=1, base=1, func="float_op_wrapper", data="&atan"},
+    atan2={args=2, base=1},
     browse={args=4},
     browsedir={args=2},
     bufadd={args=1},
@@ -66,7 +66,7 @@ return {
     byteidx={args=2},
     byteidxcomp={args=2},
     call={args={2, 3}},
-    ceil={args=1, func="float_op_wrapper", data="&ceil"},
+    ceil={args=1, base=1, func="float_op_wrapper", data="&ceil"},
     changenr={},
     chanclose={args={1, 2}},
     chansend={args=2},
@@ -81,8 +81,8 @@ return {
     complete_info={args={0, 1}},
     confirm={args={1, 4}},
     copy={args=1, base=1},
-    cos={args=1, func="float_op_wrapper", data="&cos"},
-    cosh={args=1, func="float_op_wrapper", data="&cosh"},
+    cos={args=1, base=1, func="float_op_wrapper", data="&cos"},
+    cosh={args=1, base=1, func="float_op_wrapper", data="&cosh"},
     count={args={2, 4}, base=1},
     cscope_connection={args={0, 3}},
     ctxget={args={0, 1}},
@@ -109,7 +109,7 @@ return {
     execute={args={1, 2}},
     exepath={args=1},
     exists={args=1},
-    exp={args=1, func="float_op_wrapper", data="&exp"},
+    exp={args=1, base=1, func="float_op_wrapper", data="&exp"},
     expand={args={1, 3}},
     expandcmd={args=1},
     extend={args={2, 3}, base=1},
@@ -121,9 +121,9 @@ return {
     finddir={args={1, 3}},
     findfile={args={1, 3}},
     flatten={args={1, 2}},
-    float2nr={args=1},
-    floor={args=1, func="float_op_wrapper", data="&floor"},
-    fmod={args=2},
+    float2nr={args=1, base=1},
+    floor={args=1, base=1, func="float_op_wrapper", data="&floor"},
+    fmod={args=2, base=1},
     fnameescape={args=1},
     fnamemodify={args=2},
     foldclosed={args=1},
@@ -205,9 +205,9 @@ return {
     interrupt={args=0},
     invert={args=1},
     isdirectory={args=1},
-    isinf={args=1},
+    isinf={args=1, base=1},
     islocked={args=1},
-    isnan={args=1},
+    isnan={args=1, base=1},
     id={args=1},
     items={args=1, base=1},
     jobclose={args={1, 2}, func="f_chanclose"},
@@ -230,8 +230,8 @@ return {
     lispindent={args=1},
     list2str={args={1, 2}},
     localtime={},
-    log={args=1, func="float_op_wrapper", data="&log"},
-    log10={args=1, func="float_op_wrapper", data="&log10"},
+    log={args=1, base=1, func="float_op_wrapper", data="&log"},
+    log10={args=1, base=1, func="float_op_wrapper", data="&log10"},
     luaeval={args={1, 2}},
     map={args=2, base=1},
     maparg={args={1, 4}},
@@ -256,7 +256,7 @@ return {
     nr2char={args={1, 2}},
     ['or']={args=2},
     pathshorten={args=1},
-    pow={args=2},
+    pow={args=2, base=1},
     prevnonblank={args=1},
     printf={args=varargs(1), base=2},
     prompt_getprompt={args=1},
@@ -282,7 +282,7 @@ return {
     ['repeat']={args=2, base=1},
     resolve={args=1},
     reverse={args=1, base=1},
-    round={args=1, func="float_op_wrapper", data="&round"},
+    round={args=1, base=1, func="float_op_wrapper", data="&round"},
     rpcnotify={args=varargs(2)},
     rpcrequest={args=varargs(2)},
     rpcstart={args={1, 2}},
@@ -331,8 +331,8 @@ return {
     sign_unplace={args={1, 2}},
     sign_unplacelist={args={1}},
     simplify={args=1},
-    sin={args=1, func="float_op_wrapper", data="&sin"},
-    sinh={args=1, func="float_op_wrapper", data="&sinh"},
+    sin={args=1, base=1, func="float_op_wrapper", data="&sin"},
+    sinh={args=1, base=1, func="float_op_wrapper", data="&sinh"},
     sockconnect={args={2,3}},
     sort={args={1, 3}, base=1},
     soundfold={args=1},
@@ -340,9 +340,9 @@ return {
     spellbadword={args={0, 1}},
     spellsuggest={args={1, 3}},
     split={args={1, 3}, base=1},
-    sqrt={args=1, func="float_op_wrapper", data="&sqrt"},
+    sqrt={args=1, base=1, func="float_op_wrapper", data="&sqrt"},
     stdpath={args=1},
-    str2float={args=1},
+    str2float={args=1, base=1},
     str2list={args={1, 2}, base=1},
     str2nr={args={1, 2}},
     strcharpart={args={2, 3}},
@@ -374,8 +374,8 @@ return {
     tabpagewinnr={args={1, 2}},
     tagfiles={},
     taglist={args={1, 2}},
-    tan={args=1, func="float_op_wrapper", data="&tan"},
-    tanh={args=1, func="float_op_wrapper", data="&tanh"},
+    tan={args=1, base=1, func="float_op_wrapper", data="&tan"},
+    tanh={args=1, base=1, func="float_op_wrapper", data="&tanh"},
     tempname={},
     termopen={args={1, 2}},
     test_garbagecollect_now={},
@@ -389,7 +389,7 @@ return {
     toupper={args=1},
     tr={args=3},
     trim={args={1,3}},
-    trunc={args=1, func="float_op_wrapper", data="&trunc"},
+    trunc={args=1, base=1, func="float_op_wrapper", data="&trunc"},
     type={args=1, base=1},
     undofile={args=1},
     undotree={},
diff --git a/src/nvim/testdir/test_float_func.vim b/src/nvim/testdir/test_float_func.vim
index 154ef570e0..78675d7016 100644
--- a/src/nvim/testdir/test_float_func.vim
+++ b/src/nvim/testdir/test_float_func.vim
@@ -7,6 +7,8 @@ end
 func Test_abs()
   call assert_equal('1.23', string(abs(1.23)))
   call assert_equal('1.23', string(abs(-1.23)))
+  eval -1.23->abs()->string()->assert_equal('1.23')
+
   call assert_equal('0.0', string(abs(0.0)))
   call assert_equal('0.0', string(abs(1.0/(1.0/0.0))))
   call assert_equal('0.0', string(abs(-1.0/(1.0/0.0))))
@@ -22,6 +24,7 @@ endfunc
 func Test_sqrt()
   call assert_equal('0.0', string(sqrt(0.0)))
   call assert_equal('1.414214', string(sqrt(2.0)))
+  eval 2.0->sqrt()->string()->assert_equal('1.414214')
   call assert_equal("str2float('inf')", string(sqrt(1.0/0.0)))
   call assert_equal("str2float('nan')", string(sqrt(-1.0)))
   call assert_equal("str2float('nan')", string(sqrt(0.0/0.0)))
@@ -31,6 +34,7 @@ endfunc
 func Test_log()
   call assert_equal('0.0', string(log(1.0)))
   call assert_equal('-0.693147', string(log(0.5)))
+  eval 0.5->log()->string()->assert_equal('-0.693147')
   call assert_equal("-str2float('inf')", string(log(0.0)))
   call assert_equal("str2float('nan')", string(log(-1.0)))
   call assert_equal("str2float('inf')", string(log(1.0/0.0)))
@@ -42,6 +46,7 @@ func Test_log10()
   call assert_equal('0.0', string(log10(1.0)))
   call assert_equal('2.0', string(log10(100.0)))
   call assert_equal('2.079181', string(log10(120.0)))
+  eval 120.0->log10()->string()->assert_equal('2.079181')
   call assert_equal("-str2float('inf')", string(log10(0.0)))
   call assert_equal("str2float('nan')", string(log10(-1.0)))
   call assert_equal("str2float('inf')", string(log10(1.0/0.0)))
@@ -53,6 +58,7 @@ func Test_exp()
   call assert_equal('1.0', string(exp(0.0)))
   call assert_equal('7.389056', string(exp(2.0)))
   call assert_equal('0.367879', string(exp(-1.0)))
+  eval -1.0->exp()->string()->assert_equal('0.367879')
   call assert_equal("str2float('inf')", string(exp(1.0/0.0)))
   call assert_equal('0.0', string(exp(-1.0/0.0)))
   call assert_equal("str2float('nan')", string(exp(0.0/0.0)))
@@ -63,6 +69,7 @@ func Test_sin()
   call assert_equal('0.0', string(sin(0.0)))
   call assert_equal('0.841471', string(sin(1.0)))
   call assert_equal('-0.479426', string(sin(-0.5)))
+  eval -0.5->sin()->string()->assert_equal('-0.479426')
   call assert_equal("str2float('nan')", string(sin(0.0/0.0)))
   call assert_equal("str2float('nan')", string(sin(1.0/0.0)))
   call assert_equal('0.0', string(sin(1.0/(1.0/0.0))))
@@ -73,6 +80,8 @@ endfunc
 func Test_asin()
   call assert_equal('0.0', string(asin(0.0)))
   call assert_equal('1.570796', string(asin(1.0)))
+  eval 1.0->asin()->string()->assert_equal('1.570796')
+
   call assert_equal('-0.523599', string(asin(-0.5)))
   call assert_equal("str2float('nan')", string(asin(1.1)))
   call assert_equal("str2float('nan')", string(asin(1.0/0.0)))
@@ -84,6 +93,7 @@ func Test_sinh()
   call assert_equal('0.0', string(sinh(0.0)))
   call assert_equal('0.521095', string(sinh(0.5)))
   call assert_equal('-1.026517', string(sinh(-0.9)))
+  eval -0.9->sinh()->string()->assert_equal('-1.026517')
   call assert_equal("str2float('inf')", string(sinh(1.0/0.0)))
   call assert_equal("-str2float('inf')", string(sinh(-1.0/0.0)))
   call assert_equal("str2float('nan')", string(sinh(0.0/0.0)))
@@ -94,6 +104,7 @@ func Test_cos()
   call assert_equal('1.0', string(cos(0.0)))
   call assert_equal('0.540302', string(cos(1.0)))
   call assert_equal('0.877583', string(cos(-0.5)))
+  eval -0.5->cos()->string()->assert_equal('0.877583')
   call assert_equal("str2float('nan')", string(cos(0.0/0.0)))
   call assert_equal("str2float('nan')", string(cos(1.0/0.0)))
   call assert_fails('call cos("")', 'E808:')
@@ -103,6 +114,7 @@ func Test_acos()
   call assert_equal('1.570796', string(acos(0.0)))
   call assert_equal('0.0', string(acos(1.0)))
   call assert_equal('3.141593', string(acos(-1.0)))
+  eval -1.0->acos()->string()->assert_equal('3.141593')
   call assert_equal('2.094395', string(acos(-0.5)))
   call assert_equal("str2float('nan')", string(acos(1.1)))
   call assert_equal("str2float('nan')", string(acos(1.0/0.0)))
@@ -113,6 +125,7 @@ endfunc
 func Test_cosh()
   call assert_equal('1.0', string(cosh(0.0)))
   call assert_equal('1.127626', string(cosh(0.5)))
+  eval 0.5->cosh()->string()->assert_equal('1.127626')
   call assert_equal("str2float('inf')", string(cosh(1.0/0.0)))
   call assert_equal("str2float('inf')", string(cosh(-1.0/0.0)))
   call assert_equal("str2float('nan')", string(cosh(0.0/0.0)))
@@ -123,6 +136,7 @@ func Test_tan()
   call assert_equal('0.0', string(tan(0.0)))
   call assert_equal('0.546302', string(tan(0.5)))
   call assert_equal('-0.546302', string(tan(-0.5)))
+  eval -0.5->tan()->string()->assert_equal('-0.546302')
   call assert_equal("str2float('nan')", string(tan(1.0/0.0)))
   call assert_equal("str2float('nan')", string(cos(0.0/0.0)))
   call assert_equal('0.0', string(tan(1.0/(1.0/0.0))))
@@ -134,6 +148,7 @@ func Test_atan()
   call assert_equal('0.0', string(atan(0.0)))
   call assert_equal('0.463648', string(atan(0.5)))
   call assert_equal('-0.785398', string(atan(-1.0)))
+  eval -1.0->atan()->string()->assert_equal('-0.785398')
   call assert_equal('1.570796', string(atan(1.0/0.0)))
   call assert_equal('-1.570796', string(atan(-1.0/0.0)))
   call assert_equal("str2float('nan')", string(atan(0.0/0.0)))
@@ -144,6 +159,7 @@ func Test_atan2()
   call assert_equal('-2.356194', string(atan2(-1, -1)))
   call assert_equal('2.356194', string(atan2(1, -1)))
   call assert_equal('0.0', string(atan2(1.0, 1.0/0.0)))
+  eval 1.0->atan2(1.0/0.0)->string()->assert_equal('0.0')
   call assert_equal('1.570796', string(atan2(1.0/0.0, 1.0)))
   call assert_equal("str2float('nan')", string(atan2(0.0/0.0, 1.0)))
   call assert_fails('call atan2("", -1)', 'E808:')
@@ -154,6 +170,7 @@ func Test_tanh()
   call assert_equal('0.0', string(tanh(0.0)))
   call assert_equal('0.462117', string(tanh(0.5)))
   call assert_equal('-0.761594', string(tanh(-1.0)))
+  eval -1.0->tanh()->string()->assert_equal('-0.761594')
   call assert_equal('1.0', string(tanh(1.0/0.0)))
   call assert_equal('-1.0', string(tanh(-1.0/0.0)))
   call assert_equal("str2float('nan')", string(tanh(0.0/0.0)))
@@ -164,6 +181,7 @@ func Test_fmod()
   call assert_equal('0.13', string(fmod(12.33, 1.22)))
   call assert_equal('-0.13', string(fmod(-12.33, 1.22)))
   call assert_equal("str2float('nan')", string(fmod(1.0/0.0, 1.0)))
+  eval (1.0/0.0)->fmod(1.0)->string()->assert_equal("str2float('nan')")
   " On Windows we get "nan" instead of 1.0, accept both.
   let res = string(fmod(1.0, 1.0/0.0))
   if res != "str2float('nan')"
@@ -177,6 +195,7 @@ endfunc
 func Test_pow()
   call assert_equal('1.0', string(pow(0.0, 0.0)))
   call assert_equal('8.0', string(pow(2.0, 3.0)))
+  eval 2.0->pow(3.0)->string()->assert_equal('8.0')
   call assert_equal("str2float('nan')", string(pow(2.0, 0.0/0.0)))
   call assert_equal("str2float('nan')", string(pow(0.0/0.0, 3.0)))
   call assert_equal("str2float('nan')", string(pow(0.0/0.0, 3.0)))
@@ -192,6 +211,7 @@ func Test_str2float()
   call assert_equal('1.0', string(str2float(' 1.0 ')))
   call assert_equal('1.23', string(str2float('1.23')))
   call assert_equal('1.23', string(str2float('1.23abc')))
+  eval '1.23abc'->str2float()->string()->assert_equal('1.23')
   call assert_equal('1.0e40', string(str2float('1e40')))
   call assert_equal('-1.23', string(str2float('-1.23')))
   call assert_equal('1.23', string(str2float(' + 1.23 ')))
@@ -228,6 +248,7 @@ func Test_float2nr()
   call assert_equal(1, float2nr(1.234))
   call assert_equal(123, float2nr(1.234e2))
   call assert_equal(12, float2nr(123.4e-1))
+  eval 123.4e-1->float2nr()->assert_equal(12)
   let max_number = 1/0
   let min_number = -max_number
   call assert_equal(max_number/2+1, float2nr(pow(2, 62)))
@@ -242,6 +263,7 @@ func Test_floor()
   call assert_equal('2.0', string(floor(2.0)))
   call assert_equal('2.0', string(floor(2.11)))
   call assert_equal('2.0', string(floor(2.99)))
+  eval 2.99->floor()->string()->assert_equal('2.0')
   call assert_equal('-3.0', string(floor(-2.11)))
   call assert_equal('-3.0', string(floor(-2.99)))
   call assert_equal("str2float('nan')", string(floor(0.0/0.0)))
@@ -255,6 +277,7 @@ func Test_ceil()
   call assert_equal('3.0', string(ceil(2.11)))
   call assert_equal('3.0', string(ceil(2.99)))
   call assert_equal('-2.0', string(ceil(-2.11)))
+  eval -2.11->ceil()->string()->assert_equal('-2.0')
   call assert_equal('-2.0', string(ceil(-2.99)))
   call assert_equal("str2float('nan')", string(ceil(0.0/0.0)))
   call assert_equal("str2float('inf')", string(ceil(1.0/0.0)))
@@ -266,6 +289,7 @@ func Test_round()
   call assert_equal('2.0', string(round(2.1)))
   call assert_equal('3.0', string(round(2.5)))
   call assert_equal('3.0', string(round(2.9)))
+  eval 2.9->round()->string()->assert_equal('3.0')
   call assert_equal('-2.0', string(round(-2.1)))
   call assert_equal('-3.0', string(round(-2.5)))
   call assert_equal('-3.0', string(round(-2.9)))
@@ -279,6 +303,7 @@ func Test_trunc()
   call assert_equal('2.0', string(trunc(2.1)))
   call assert_equal('2.0', string(trunc(2.5)))
   call assert_equal('2.0', string(trunc(2.9)))
+  eval 2.9->trunc()->string()->assert_equal('2.0')
   call assert_equal('-2.0', string(trunc(-2.1)))
   call assert_equal('-2.0', string(trunc(-2.5)))
   call assert_equal('-2.0', string(trunc(-2.9)))
@@ -291,6 +316,7 @@ endfunc
 func Test_isinf()
   call assert_equal(1, isinf(1.0/0.0))
   call assert_equal(-1, isinf(-1.0/0.0))
+  eval (-1.0/0.0)->isinf()->assert_equal(-1)
   call assert_false(isinf(1.0))
   call assert_false(isinf(0.0/0.0))
   call assert_false(isinf('a'))
@@ -302,6 +328,7 @@ func Test_isnan()
   call assert_true(isnan(0.0/0.0))
   call assert_false(isnan(1.0))
   call assert_false(isnan(1.0/0.0))
+  eval (1.0/0.0)->isnan()->assert_false()
   call assert_false(isnan(-1.0/0.0))
   call assert_false(isnan('a'))
   call assert_false(isnan([]))